20640606460 has 12 divisors (see below), whose sum is σ = 43345273608. Its totient is φ = 8256242576.

The previous prime is 20640606419. The next prime is 20640606461. The reversal of 20640606460 is 6460604602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20640606461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 516015142 + ... + 516015181.

It is an arithmetic number, because the mean of its divisors is an integer number (3612106134).

Almost surely, 2^20640606460 is an apocalyptic number.

20640606460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20640606460 is an abundant number, since it is smaller than the sum of its proper divisors (22704667148).

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

20640606460 is a wasteful number, since it uses less digits than its factorization.

20640606460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1032030332 (or 1032030330 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 34.

The spelling of 20640606460 in words is "twenty billion, six hundred forty million, six hundred six thousand, four hundred sixty".