131615551 has 4 divisors (see below), whose sum is σ = 131658592. Its totient is φ = 131572512.

The previous prime is 131615521. The next prime is 131615573. The reversal of 131615551 is 155516131.

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

It is a cyclic number.

It is not a de Polignac number, because 131615551 - 2¹⁵ = 131582783 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 (131615521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16551 + ... + 23176.

It is an arithmetic number, because the mean of its divisors is an integer number (32914648).

Almost surely, 2^131615551 is an apocalyptic number.

131615551 is a deficient number, since it is larger than the sum of its proper divisors (43041).

131615551 is an equidigital number, since it uses as much as digits as its factorization.

131615551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43040.

The product of its digits is 2250, while the sum is 28.

The square root of 131615551 is about 11472.3820978906. The cubic root of 131615551 is about 508.6695438695.

The spelling of 131615551 in words is "one hundred thirty-one million, six hundred fifteen thousand, five hundred fifty-one".