28571931 has 12 divisors (see below), whose sum is σ = 42694080. Its totient is φ = 18390960.

The previous prime is 28571923. The next prime is 28571947. The reversal of 28571931 is 13917582.

It is not a de Polignac number, because 28571931 - 2³ = 28571923 is a prime.

It is a super-2 number, since 2×28571931² = 1632710482137522, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (28571131) 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, 54475 + ... + 54996.

It is an arithmetic number, because the mean of its divisors is an integer number (3557840).

Almost surely, 2^28571931 is an apocalyptic number.

28571931 is a deficient number, since it is larger than the sum of its proper divisors (14122149).

28571931 is a wasteful number, since it uses less digits than its factorization.

28571931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109506 (or 109503 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 28571931 is about 5345.2718359313. The cubic root of 28571931 is about 305.7125006966.

The spelling of 28571931 in words is "twenty-eight million, five hundred seventy-one thousand, nine hundred thirty-one".