20647837660 has 24 divisors (see below), whose sum is σ = 43393338576. Its totient is φ = 8252872320.

The previous prime is 20647837621. The next prime is 20647837663. The reversal of 20647837660 is 6673874602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20647837663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 364342 + ... + 417181.

It is an arithmetic number, because the mean of its divisors is an integer number (1808055774).

Almost surely, 2^20647837660 is an apocalyptic number.

20647837660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20647837660 is an abundant number, since it is smaller than the sum of its proper divisors (22745500916).

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

20647837660 is a wasteful number, since it uses less digits than its factorization.

20647837660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 782853 (or 782851 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 49.

The spelling of 20647837660 in words is "twenty billion, six hundred forty-seven million, eight hundred thirty-seven thousand, six hundred sixty".