20659491 has 12 divisors (see below), whose sum is σ = 29952832. Its totient is φ = 13721616.

The previous prime is 20659427. The next prime is 20659493. The reversal of 20659491 is 19495602.

It is not a de Polignac number, because 20659491 - 2⁶ = 20659427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20659493) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1651 + ... + 6636.

Almost surely, 2^20659491 is an apocalyptic number.

20659491 is a deficient number, since it is larger than the sum of its proper divisors (9293341).

20659491 is a wasteful number, since it uses less digits than its factorization.

20659491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8570 (or 8567 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 20659491 is about 4545.2712790327. The cubic root of 20659491 is about 274.3931123553.

The spelling of 20659491 in words is "twenty million, six hundred fifty-nine thousand, four hundred ninety-one".