102216420 has 72 divisors (see below), whose sum is σ = 312117624. Its totient is φ = 27076608.

The previous prime is 102216407. The next prime is 102216421. The reversal of 102216420 is 24612201.

102216420 is a `hidden beast` number, since 1 + 0 + 2 + 21 + 642 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2056356 + 100160064 = 1434^2 + 10008^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 102216393 and 102216402.

It is not an unprimeable number, because it can be changed into a prime (102216421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26452 + ... + 30068.

It is an arithmetic number, because the mean of its divisors is an integer number (4334967).

Almost surely, 2^102216420 is an apocalyptic number.

102216420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 102216420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156058812).

102216420 is an abundant number, since it is smaller than the sum of its proper divisors (209901204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

102216420 is a wasteful number, since it uses less digits than its factorization.

102216420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3789 (or 3784 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 102216420 is about 10110.2136475942. The cubic root of 102216420 is about 467.5630921360.

Adding to 102216420 its reverse (24612201), we get a palindrome (126828621).

It can be divided in two parts, 10221 and 6420, that added together give a square (16641 = 129²).

The spelling of 102216420 in words is "one hundred two million, two hundred sixteen thousand, four hundred twenty".