21021010012100 has 72 divisors (see below), whose sum is σ = 52132923571008. Its totient is φ = 7207090243200.

The previous prime is 21021010012069. The next prime is 21021010012129. The reversal of 21021010012100 is 121001012012.

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, 52920230 + ... + 53315970.

Almost surely, 2^{21021010012100} is an apocalyptic number.

21021010012100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021010012100 is an abundant number, since it is smaller than the sum of its proper divisors (31111913558908).

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

21021010012100 is a wasteful number, since it uses less digits than its factorization.

21021010012100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471645 (or 471638 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21021010012100 its reverse (121001012012), we get a palindrome (21142011024112).

The spelling of 21021010012100 in words is "twenty-one trillion, twenty-one billion, ten million, twelve thousand, one hundred".