20571897 has 16 divisors (see below), whose sum is σ = 28226880. Its totient is φ = 13321152.

The previous prime is 20571893. The next prime is 20571899. The reversal of 20571897 is 79817502.

It is not a de Polignac number, because 20571897 - 2² = 20571893 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20571893) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16738 + ... + 17924.

It is an arithmetic number, because the mean of its divisors is an integer number (1764180).

Almost surely, 2^20571897 is an apocalyptic number.

It is an amenable number.

20571897 is a deficient number, since it is larger than the sum of its proper divisors (7654983).

20571897 is a wasteful number, since it uses less digits than its factorization.

20571897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1352.

The product of its (nonzero) digits is 35280, while the sum is 39.

The square root of 20571897 is about 4535.6253152129. The cubic root of 20571897 is about 274.0047639785.

The spelling of 20571897 in words is "twenty million, five hundred seventy-one thousand, eight hundred ninety-seven".