15131261 has 4 divisors (see below), whose sum is σ = 15540252. Its totient is φ = 14722272.

The previous prime is 15131231. The next prime is 15131273. The reversal of 15131261 is 16213151.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7672900 + 7458361 = 2770^2 + 2731^2 .

It is a cyclic number.

It is not a de Polignac number, because 15131261 - 2⁶ = 15131197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15131231) 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, 204440 + ... + 204513.

It is an arithmetic number, because the mean of its divisors is an integer number (3885063).

Almost surely, 2^15131261 is an apocalyptic number.

It is an amenable number.

15131261 is a deficient number, since it is larger than the sum of its proper divisors (408991).

15131261 is an equidigital number, since it uses as much as digits as its factorization.

15131261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 408990.

The product of its digits is 180, while the sum is 20.

The square root of 15131261 is about 3889.8921578882. The cubic root of 15131261 is about 247.3384913707.

The spelling of 15131261 in words is "fifteen million, one hundred thirty-one thousand, two hundred sixty-one".