21012696940 has 24 divisors (see below), whose sum is σ = 44959244400. Its totient is φ = 8246491968.

The previous prime is 21012696931. The next prime is 21012696959. The reversal of 21012696940 is 4969621012.

It is a junction number, because it is equal to n+sod(n) for n = 21012696893 and 21012696902.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9910590 + ... + 9912709.

It is an arithmetic number, because the mean of its divisors is an integer number (1873301850).

Almost surely, 2^21012696940 is an apocalyptic number.

21012696940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21012696940 is an abundant number, since it is smaller than the sum of its proper divisors (23946547460).

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

21012696940 is a wasteful number, since it uses less digits than its factorization.

21012696940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19823361 (or 19823359 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 40.

The spelling of 21012696940 in words is "twenty-one billion, twelve million, six hundred ninety-six thousand, nine hundred forty".