102011220 has 216 divisors, whose sum is σ = 343960344. Its totient is φ = 24440832.

The previous prime is 102011219. The next prime is 102011227. The reversal of 102011220 is 22110201.

It can be written as a sum of positive squares in 12 ways, for example, as 3048516 + 98962704 = 1746^2 + 9948^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102011227) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1924714 + ... + 1924766.

It is an arithmetic number, because the mean of its divisors is an integer number (1592409).

Almost surely, 2^102011220 is an apocalyptic number.

102011220 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 102011220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171980172).

102011220 is an abundant number, since it is smaller than the sum of its proper divisors (241949124).

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

102011220 is a wasteful number, since it uses less digits than its factorization.

102011220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 102011220 is about 10100.0603958590. The cubic root of 102011220 is about 467.2500040794.

Adding to 102011220 its reverse (22110201), we get a palindrome (124121421).

The spelling of 102011220 in words is "one hundred two million, eleven thousand, two hundred twenty".