20495691 has 12 divisors (see below), whose sum is σ = 30892368. Its totient is φ = 13069584.

The previous prime is 20495687. The next prime is 20495701. The reversal of 20495691 is 19659402.

It is not a de Polignac number, because 20495691 - 2² = 20495687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20495191) 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, 49300 + ... + 49713.

It is an arithmetic number, because the mean of its divisors is an integer number (2574364).

Almost surely, 2^20495691 is an apocalyptic number.

20495691 is a deficient number, since it is larger than the sum of its proper divisors (10396677).

20495691 is a wasteful number, since it uses less digits than its factorization.

20495691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99042 (or 99039 counting only the distinct ones).

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

The square root of 20495691 is about 4527.2166946149. The cubic root of 20495691 is about 273.6660066327. Note that the first 3 decimals are identical.

The spelling of 20495691 in words is "twenty million, four hundred ninety-five thousand, six hundred ninety-one".