15117231 has 4 divisors (see below), whose sum is σ = 20156312. Its totient is φ = 10078152.

The previous prime is 15117229. The next prime is 15117239. The reversal of 15117231 is 13271151.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13271151 = 3 ⋅4423717.

It is not a de Polignac number, because 15117231 - 2¹ = 15117229 is a prime.

It is a super-2 number, since 2×15117231² = 457061346214722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15117198 and 15117207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15117239) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2519536 + ... + 2519541.

It is an arithmetic number, because the mean of its divisors is an integer number (5039078).

Almost surely, 2^15117231 is an apocalyptic number.

15117231 is a deficient number, since it is larger than the sum of its proper divisors (5039081).

15117231 is an equidigital number, since it uses as much as digits as its factorization.

15117231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5039080.

The product of its digits is 210, while the sum is 21.

The square root of 15117231 is about 3888.0883477617. The cubic root of 15117231 is about 247.2620220418.

Adding to 15117231 its reverse (13271151), we get a palindrome (28388382).

The spelling of 15117231 in words is "fifteen million, one hundred seventeen thousand, two hundred thirty-one".