20087971 has 8 divisors (see below), whose sum is σ = 20585984. Its totient is φ = 19595520.

The previous prime is 20087953. The next prime is 20087989. The reversal of 20087971 is 17978002.

It is an interprime number because it is at equal distance from previous prime (20087953) and next prime (20087989).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 8-Lehmer number, since φ(20087971) divides (20087971-1)⁸.

It is a cyclic number.

It is not a de Polignac number, because 20087971 - 2⁵ = 20087939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20084971) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6451 + ... + 9043.

It is an arithmetic number, because the mean of its divisors is an integer number (2573248).

Almost surely, 2^20087971 is an apocalyptic number.

20087971 is a deficient number, since it is larger than the sum of its proper divisors (498013).

20087971 is a wasteful number, since it uses less digits than its factorization.

20087971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2781.

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 20087971 is about 4481.9606200858. The cubic root of 20087971 is about 271.8391629515.

The spelling of 20087971 in words is "twenty million, eighty-seven thousand, nine hundred seventy-one".