21001211022100 has 72 divisors (see below), whose sum is σ = 48276736931360. Its totient is φ = 7907663387520.

The previous prime is 21001211022047. The next prime is 21001211022101. The reversal of 21001211022100 is 122011210012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001211022101) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34903194 + ... + 35499793.

Almost surely, 2^{21001211022100} is an apocalyptic number.

21001211022100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001211022100 is an abundant number, since it is smaller than the sum of its proper divisors (27275525909260).

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

21001211022100 is a wasteful number, since it uses less digits than its factorization.

21001211022100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70403177 (or 70403170 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21001211022100 its reverse (122011210012), we get a palindrome (21123222232112).

The spelling of 21001211022100 in words is "twenty-one trillion, one billion, two hundred eleven million, twenty-two thousand, one hundred".