20656977 has 8 divisors (see below), whose sum is σ = 30046560. Its totient is φ = 12519360.

The previous prime is 20656973. The next prime is 20656991. The reversal of 20656977 is 77965602.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20656977 - 2² = 20656973 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (20656973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 312952 + ... + 313017.

It is an arithmetic number, because the mean of its divisors is an integer number (3755820).

Almost surely, 2^20656977 is an apocalyptic number.

It is an amenable number.

20656977 is a deficient number, since it is larger than the sum of its proper divisors (9389583).

20656977 is a wasteful number, since it uses less digits than its factorization.

20656977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 625983.

The product of its (nonzero) digits is 158760, while the sum is 42.

The square root of 20656977 is about 4544.9947194689. The cubic root of 20656977 is about 274.3819818412.

The spelling of 20656977 in words is "twenty million, six hundred fifty-six thousand, nine hundred seventy-seven".