13228731 has 32 divisors (see below), whose sum is σ = 20908800. Its totient is φ = 8242560.

The previous prime is 13228717. The next prime is 13228741. The reversal of 13228731 is 13782231.

It is not a de Polignac number, because 13228731 - 2⁷ = 13228603 is a prime.

It is a super-2 number, since 2×13228731² = 349998647740722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 13228695 and 13228704.

It is not an unprimeable number, because it can be changed into a prime (13228741) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 54771 + ... + 55011.

It is an arithmetic number, because the mean of its divisors is an integer number (653400).

Almost surely, 2^13228731 is an apocalyptic number.

13228731 is a deficient number, since it is larger than the sum of its proper divisors (7680069).

13228731 is a wasteful number, since it uses less digits than its factorization.

13228731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376 (or 370 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 13228731 is about 3637.1322494515. The cubic root of 13228731 is about 236.5044927013.

The spelling of 13228731 in words is "thirteen million, two hundred twenty-eight thousand, seven hundred thirty-one".