21201012100100 has 72 divisors (see below), whose sum is σ = 53860912764288. Its totient is φ = 7091627731200.

The previous prime is 21201012100049. The next prime is 21201012100171. The reversal of 21201012100100 is 100121010212.

It is a super-2 number, since 2×21201012100100² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 369326912 + ... + 369384311.

Almost surely, 2^{21201012100100} is an apocalyptic number.

21201012100100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201012100100 is an abundant number, since it is smaller than the sum of its proper divisors (32659900664188).

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

21201012100100 is a wasteful number, since it uses less digits than its factorization.

21201012100100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 738711285 (or 738711278 counting only the distinct ones).

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

Adding to 21201012100100 its reverse (100121010212), we get a palindrome (21301133110312).

The spelling of 21201012100100 in words is "twenty-one trillion, two hundred one billion, twelve million, one hundred thousand, one hundred".