20644540677 has 24 divisors (see below), whose sum is σ = 30860263200. Its totient is φ = 13283228448.

The previous prime is 20644540667. The next prime is 20644540717. The reversal of 20644540677 is 77604544602.

20644540677 is a `hidden beast` number, since 2 + 0 + 6 + 44 + 540 + 67 + 7 = 666.

It is not a de Polignac number, because 20644540677 - 2¹⁵ = 20644507909 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20644540627) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 717474 + ... + 745692.

It is an arithmetic number, because the mean of its divisors is an integer number (1285844300).

Almost surely, 2^20644540677 is an apocalyptic number.

It is an amenable number.

20644540677 is a deficient number, since it is larger than the sum of its proper divisors (10215722523).

20644540677 is a wasteful number, since it uses less digits than its factorization.

20644540677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31057 (or 31054 counting only the distinct ones).

The product of its (nonzero) digits is 1128960, while the sum is 45.

The spelling of 20644540677 in words is "twenty billion, six hundred forty-four million, five hundred forty thousand, six hundred seventy-seven".