102101220 has 72 divisors (see below), whose sum is σ = 333538296. Its totient is φ = 25132032.

The previous prime is 102101213. The next prime is 102101239. The reversal of 102101220 is 22101201.

It can be written as a sum of positive squares in 4 ways, for example, as 14379264 + 87721956 = 3792^2 + 9366^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19477 + ... + 24156.

Almost surely, 2^102101220 is an apocalyptic number.

102101220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

102101220 is an abundant number, since it is smaller than the sum of its proper divisors (231437076).

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

102101220 is a wasteful number, since it uses less digits than its factorization.

102101220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43661 (or 43656 counting only the distinct ones).

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

The square root of 102101220 is about 10104.5148324895. The cubic root of 102101220 is about 467.3873750451.

Adding to 102101220 its reverse (22101201), we get a palindrome (124202421).

The spelling of 102101220 in words is "one hundred two million, one hundred one thousand, two hundred twenty".