21210021002120 has 64 divisors (see below), whose sum is σ = 47751317640000. Its totient is φ = 8478895212288.

The previous prime is 21210021002101. The next prime is 21210021002171. The reversal of 21210021002120 is 2120012001212.

It is a junction number, because it is equal to n+sod(n) for n = 21210021002095 and 21210021002104.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 519591071 + ... + 519631889.

It is an arithmetic number, because the mean of its divisors is an integer number (746114338125).

Almost surely, 2^{21210021002120} is an apocalyptic number.

21210021002120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210021002120 is an abundant number, since it is smaller than the sum of its proper divisors (26541296637880).

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

21210021002120 is a wasteful number, since it uses less digits than its factorization.

21210021002120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48342 (or 48338 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21210021002120 its reverse (2120012001212), we get a palindrome (23330033003332).

The spelling of 21210021002120 in words is "twenty-one trillion, two hundred ten billion, twenty-one million, two thousand, one hundred twenty".