20871959 has 12 divisors (see below), whose sum is σ = 22187592. Its totient is φ = 19619280.

The previous prime is 20871923. The next prime is 20871973. The reversal of 20871959 is 95917802.

It is not a de Polignac number, because 20871959 - 2¹² = 20867863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20871659) 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, 35264 + ... + 35850.

It is an arithmetic number, because the mean of its divisors is an integer number (1848966).

Almost surely, 2^20871959 is an apocalyptic number.

20871959 is a deficient number, since it is larger than the sum of its proper divisors (1315633).

20871959 is an equidigital number, since it uses as much as digits as its factorization.

20871959 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686 (or 655 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 41.

The square root of 20871959 is about 4568.5839162699. The cubic root of 20871959 is about 275.3305512770.

The spelling of 20871959 in words is "twenty million, eight hundred seventy-one thousand, nine hundred fifty-nine".