28786731 has 16 divisors (see below), whose sum is σ = 40565760. Its totient is φ = 18120960.

The previous prime is 28786721. The next prime is 28786741. The reversal of 28786731 is 13768782.

It is an interprime number because it is at equal distance from previous prime (28786721) and next prime (28786741).

It is not a de Polignac number, because 28786731 - 2¹¹ = 28784683 is a prime.

It is a super-2 number, since 2×28786731² = 1657351763332722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28786711) 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, 2811 + ... + 8091.

It is an arithmetic number, because the mean of its divisors is an integer number (2535360).

Almost surely, 2^28786731 is an apocalyptic number.

28786731 is a deficient number, since it is larger than the sum of its proper divisors (11779029).

28786731 is a wasteful number, since it uses less digits than its factorization.

28786731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5386.

The product of its digits is 112896, while the sum is 42.

The square root of 28786731 is about 5365.3267374877. The cubic root of 28786731 is about 306.4766909118.

The spelling of 28786731 in words is "twenty-eight million, seven hundred eighty-six thousand, seven hundred thirty-one".