20656057 has 2 divisors, whose sum is σ = 20656058. Its totient is φ = 20656056.

The previous prime is 20655997. The next prime is 20656067. The reversal of 20656057 is 75065602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14584761 + 6071296 = 3819^2 + 2464^2 .

It is a cyclic number.

It is not a de Polignac number, because 20656057 - 2¹⁵ = 20623289 is a prime.

It is not a weakly prime, because it can be changed into another prime (20656067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10328028 + 10328029.

It is an arithmetic number, because the mean of its divisors is an integer number (10328029).

Almost surely, 2^20656057 is an apocalyptic number.

It is an amenable number.

20656057 is a deficient number, since it is larger than the sum of its proper divisors (1).

20656057 is an equidigital number, since it uses as much as digits as its factorization.

20656057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12600, while the sum is 31.

The square root of 20656057 is about 4544.8935081034. The cubic root of 20656057 is about 274.3779083964.

The spelling of 20656057 in words is "twenty million, six hundred fifty-six thousand, fifty-seven".