20516977 has 24 divisors (see below), whose sum is σ = 24206336. Its totient is φ = 17273088.

The previous prime is 20516953. The next prime is 20516999. The reversal of 20516977 is 77961502.

It is not a de Polignac number, because 20516977 - 2⁷ = 20516849 is a prime.

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20516077) 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, 161488 + ... + 161614.

Almost surely, 2^20516977 is an apocalyptic number.

It is an amenable number.

20516977 is a deficient number, since it is larger than the sum of its proper divisors (3689359).

20516977 is a wasteful number, since it uses less digits than its factorization.

20516977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217 (or 200 counting only the distinct ones).

The product of its (nonzero) digits is 26460, while the sum is 37.

The square root of 20516977 is about 4529.5669770962. The cubic root of 20516977 is about 273.7607133551.

The spelling of 20516977 in words is "twenty million, five hundred sixteen thousand, nine hundred seventy-seven".