21206210057600 has 96 divisors (see below), whose sum is σ = 52392444697200. Its totient is φ = 8481434941440.

The previous prime is 21206210057563. The next prime is 21206210057609. The reversal of 21206210057600 is 675001260212.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21206210057609) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 25728686 + ... + 26540114.

Almost surely, 2^{21206210057600} is an apocalyptic number.

21206210057600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21206210057600 is an abundant number, since it is smaller than the sum of its proper divisors (31186234639600).

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

21206210057600 is an equidigital number, since it uses as much as digits as its factorization.

21206210057600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 819620 (or 819603 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The spelling of 21206210057600 in words is "twenty-one trillion, two hundred six billion, two hundred ten million, fifty-seven thousand, six hundred".