28379731 has 4 divisors (see below), whose sum is σ = 28403200. Its totient is φ = 28356264.

The previous prime is 28379713. The next prime is 28379753. The reversal of 28379731 is 13797382.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28379731 - 2²¹ = 26282579 is a prime.

It is a super-2 number, since 2×28379731² = 1610818263264722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28379431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9816 + ... + 12373.

It is an arithmetic number, because the mean of its divisors is an integer number (7100800).

Almost surely, 2^28379731 is an apocalyptic number.

28379731 is a deficient number, since it is larger than the sum of its proper divisors (23469).

28379731 is a wasteful number, since it uses less digits than its factorization.

28379731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23468.

The product of its digits is 63504, while the sum is 40.

The square root of 28379731 is about 5327.2629933203. The cubic root of 28379731 is about 305.0254605638.

The spelling of 28379731 in words is "twenty-eight million, three hundred seventy-nine thousand, seven hundred thirty-one".