15551131 has 2 divisors, whose sum is σ = 15551132. Its totient is φ = 15551130.

The previous prime is 15551111. The next prime is 15551147. The reversal of 15551131 is 13115551.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 15551131 - 2⁵ = 15551099 is a prime.

It is a super-2 number, since 2×15551131² = 483675350758322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (15551111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7775565 + 7775566.

It is an arithmetic number, because the mean of its divisors is an integer number (7775566).

Almost surely, 2^15551131 is an apocalyptic number.

15551131 is a deficient number, since it is larger than the sum of its proper divisors (1).

15551131 is an equidigital number, since it uses as much as digits as its factorization.

15551131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 375, while the sum is 22.

The square root of 15551131 is about 3943.4922340484. The cubic root of 15551131 is about 249.6054095211.

Adding to 15551131 its reverse (13115551), we get a palindrome (28666682).

The spelling of 15551131 in words is "fifteen million, five hundred fifty-one thousand, one hundred thirty-one".