20157507 has 6 divisors (see below), whose sum is σ = 29116412. Its totient is φ = 13438332.

The previous prime is 20157503. The next prime is 20157509. The reversal of 20157507 is 70575102.

20157507 is a `hidden beast` number, since 2 + 0 + 157 + 507 = 666.

It is not a de Polignac number, because 20157507 - 2² = 20157503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20157503) 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, 1119853 + ... + 1119870.

Almost surely, 2^20157507 is an apocalyptic number.

20157507 is a deficient number, since it is larger than the sum of its proper divisors (8958905).

20157507 is a wasteful number, since it uses less digits than its factorization.

20157507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2239729 (or 2239726 counting only the distinct ones).

The product of its (nonzero) digits is 2450, while the sum is 27.

The square root of 20157507 is about 4489.7112379306. The cubic root of 20157507 is about 272.1524655238.

The spelling of 20157507 in words is "twenty million, one hundred fifty-seven thousand, five hundred seven".