23278731 has 16 divisors (see below), whose sum is σ = 35606784. Its totient is φ = 13251744.

The previous prime is 23278727. The next prime is 23278753. The reversal of 23278731 is 13787232.

It is not a de Polignac number, because 23278731 - 2² = 23278727 is a prime.

It is a super-2 number, since 2×23278731² = 1083798633940722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 23278692 and 23278701.

It is not an unprimeable number, because it can be changed into a prime (23278711) 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, 3985 + ... + 7901.

It is an arithmetic number, because the mean of its divisors is an integer number (2225424).

Almost surely, 2^23278731 is an apocalyptic number.

23278731 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

23278731 is a deficient number, since it is larger than the sum of its proper divisors (12328053).

23278731 is a wasteful number, since it uses less digits than its factorization.

23278731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4210.

The product of its digits is 14112, while the sum is 33.

The square root of 23278731 is about 4824.8037265779. The cubic root of 23278731 is about 285.5308910337.

The spelling of 23278731 in words is "twenty-three million, two hundred seventy-eight thousand, seven hundred thirty-one".