20164657 has 6 divisors (see below), whose sum is σ = 20884838. Its totient is φ = 19468512.

The previous prime is 20164649. The next prime is 20164733. The reversal of 20164657 is 75646102.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 2825761 + 17338896 = 1681^2 + 4164^2 .

It is not a de Polignac number, because 20164657 - 2³ = 20164649 is a prime.

It is a super-2 number, since 2×20164657² = 813226783855298, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20164357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11148 + ... + 12829.

Almost surely, 2^20164657 is an apocalyptic number.

It is an amenable number.

20164657 is a deficient number, since it is larger than the sum of its proper divisors (720181).

20164657 is an equidigital number, since it uses as much as digits as its factorization.

20164657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24035 (or 24006 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 20164657 is about 4490.5074323510. The cubic root of 20164657 is about 272.1846398084.

The spelling of 20164657 in words is "twenty million, one hundred sixty-four thousand, six hundred fifty-seven".