28747731 has 16 divisors (see below), whose sum is σ = 40994208. Its totient is φ = 17856000.

The previous prime is 28747717. The next prime is 28747759. The reversal of 28747731 is 13774782.

It is not a de Polignac number, because 28747731 - 2²³ = 20359123 is a prime.

It is a super-2 number, since 2×28747731² = 1652864075296722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28747731.

It is not an unprimeable number, because it can be changed into a prime (28747711) 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, 2361 + ... + 7941.

It is an arithmetic number, because the mean of its divisors is an integer number (2562138).

Almost surely, 2^28747731 is an apocalyptic number.

28747731 is a deficient number, since it is larger than the sum of its proper divisors (12246477).

28747731 is a wasteful number, since it uses less digits than its factorization.

28747731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5702.

The product of its digits is 65856, while the sum is 39.

The square root of 28747731 is about 5361.6910578660. The cubic root of 28747731 is about 306.3382244222.

The spelling of 28747731 in words is "twenty-eight million, seven hundred forty-seven thousand, seven hundred thirty-one".