21321012320100 has 216 divisors, whose sum is σ = 71656386197760. Its totient is φ = 5283419581440.

The previous prime is 21321012320099. The next prime is 21321012320161. The reversal of 21321012320100 is 102321012312.

21321012320100 is a `hidden beast` number, since 2 + 1 + 321 + 0 + 12 + 320 + 10 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 7611112 + ... + 10028511.

Almost surely, 2^{21321012320100} is an apocalyptic number.

21321012320100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21321012320100 is an abundant number, since it is smaller than the sum of its proper divisors (50335373877660).

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

21321012320100 is a wasteful number, since it uses less digits than its factorization.

21321012320100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17639739 (or 17639729 counting only the distinct ones).

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

Adding to 21321012320100 its reverse (102321012312), we get a palindrome (21423333332412).

The spelling of 21321012320100 in words is "twenty-one trillion, three hundred twenty-one billion, twelve million, three hundred twenty thousand, one hundred".