21221313102 has 48 divisors (see below), whose sum is σ = 51105897648. Its totient is φ = 6309363840.

The previous prime is 21221313083. The next prime is 21221313109. The reversal of 21221313102 is 20131312212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221313109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1000623 + ... + 1021610.

It is an arithmetic number, because the mean of its divisors is an integer number (1064706201).

Almost surely, 2^21221313102 is an apocalyptic number.

21221313102 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21221313102 is an abundant number, since it is smaller than the sum of its proper divisors (29884584546).

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

21221313102 is a wasteful number, since it uses less digits than its factorization.

21221313102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2022305 (or 2022302 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21221313102 its reverse (20131312212), we get a palindrome (41352625314).

The spelling of 21221313102 in words is "twenty-one billion, two hundred twenty-one million, three hundred thirteen thousand, one hundred two".