28038731 has 12 divisors (see below), whose sum is σ = 32722560. Its totient is φ = 23955120.

The previous prime is 28038713. The next prime is 28038733. The reversal of 28038731 is 13783082.

It is not a de Polignac number, because 28038731 - 2⁶ = 28038667 is a prime.

It is a super-2 number, since 2×28038731² = 1572340872180722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28038733) 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, 18326 + ... + 19796.

It is an arithmetic number, because the mean of its divisors is an integer number (2726880).

Almost surely, 2^28038731 is an apocalyptic number.

28038731 is a deficient number, since it is larger than the sum of its proper divisors (4683829).

28038731 is a wasteful number, since it uses less digits than its factorization.

28038731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1874 (or 1867 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 28038731 is about 5295.1610929225. The cubic root of 28038731 is about 303.7988447364.

The spelling of 28038731 in words is "twenty-eight million, thirty-eight thousand, seven hundred thirty-one".