102121220 has 24 divisors (see below), whose sum is σ = 214943064. Its totient is φ = 40755456.

The previous prime is 102121213. The next prime is 102121231. The reversal of 102121220 is 22121201.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 24364096 + 77757124 = 4936^2 + 8818^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3554 + ... + 14726.

It is an arithmetic number, because the mean of its divisors is an integer number (8955961).

Almost surely, 2^102121220 is an apocalyptic number.

102121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

102121220 is an abundant number, since it is smaller than the sum of its proper divisors (112821844).

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

102121220 is a wasteful number, since it uses less digits than its factorization.

102121220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11639 (or 11637 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 102121220 is about 10105.5044406502. The cubic root of 102121220 is about 467.4178909625.

Adding to 102121220 its reverse (22121201), we get a palindrome (124242421).

The spelling of 102121220 in words is "one hundred two million, one hundred twenty-one thousand, two hundred twenty".