21012221020102 has 48 divisors (see below), whose sum is σ = 34641041495760. Its totient is φ = 9552559775616.

The previous prime is 21012221020073. The next prime is 21012221020127. The reversal of 21012221020102 is 20102012221012.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 551931924 + ... + 551969992.

It is an arithmetic number, because the mean of its divisors is an integer number (721688364495).

Almost surely, 2^{21012221020102} is an apocalyptic number.

21012221020102 is a deficient number, since it is larger than the sum of its proper divisors (13628820475658).

21012221020102 is a wasteful number, since it uses less digits than its factorization.

21012221020102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62537 (or 62524 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21012221020102 its reverse (20102012221012), we get a palindrome (41114233241114).

The spelling of 21012221020102 in words is "twenty-one trillion, twelve billion, two hundred twenty-one million, twenty thousand, one hundred two".