20565942660 has 96 divisors (see below), whose sum is σ = 66764839680. Its totient is φ = 5245802496.

The previous prime is 20565942659. The next prime is 20565942667. The reversal of 20565942660 is 6624956502.

It is a happy number.

20565942660 is a `hidden beast` number, since 2 + 0 + 56 + 594 + 2 + 6 + 6 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (20565942667) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 815517 + ... + 840356.

It is an arithmetic number, because the mean of its divisors is an integer number (695467080).

Almost surely, 2^20565942660 is an apocalyptic number.

20565942660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20565942660 is an abundant number, since it is smaller than the sum of its proper divisors (46198897020).

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

20565942660 is a wasteful number, since it uses less digits than its factorization.

20565942660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1655914 (or 1655906 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 45.

The spelling of 20565942660 in words is "twenty billion, five hundred sixty-five million, nine hundred forty-two thousand, six hundred sixty".