21000002102120 has 64 divisors (see below), whose sum is σ = 47285974679040. Its totient is φ = 8393607417600.

The previous prime is 21000002102099. The next prime is 21000002102207. The reversal of 21000002102120 is 2120120000012.

It is a happy number.

It is a super-3 number, since 3×21000002102120³ (a number of 41 digits) contains 333 as substring.

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, 1110455465 + ... + 1110474375.

It is an arithmetic number, because the mean of its divisors is an integer number (738843354360).

Almost surely, 2^{21000002102120} is an apocalyptic number.

21000002102120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000002102120 is an abundant number, since it is smaller than the sum of its proper divisors (26285972576920).

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

21000002102120 is a wasteful number, since it uses less digits than its factorization.

21000002102120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38586 (or 38582 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21000002102120 its reverse (2120120000012), we get a palindrome (23120122102132).

The spelling of 21000002102120 in words is "twenty-one trillion, two million, one hundred two thousand, one hundred twenty".