15132991 has 4 divisors (see below), whose sum is σ = 15621184. Its totient is φ = 14644800.

The previous prime is 15132967. The next prime is 15133031. The reversal of 15132991 is 19923151.

It is a happy number.

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 15132991 - 2¹¹ = 15130943 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31), and also a Moran number because the ratio is a prime number: 488161 = 15132991 / (1 + 5 + 1 + 3 + 2 + 9 + 9 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15132961) 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, 244050 + ... + 244111.

It is an arithmetic number, because the mean of its divisors is an integer number (3905296).

Almost surely, 2^15132991 is an apocalyptic number.

15132991 is a deficient number, since it is larger than the sum of its proper divisors (488193).

15132991 is an equidigital number, since it uses as much as digits as its factorization.

15132991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488192.

The product of its digits is 2430, while the sum is 31.

The square root of 15132991 is about 3890.1145227358. The cubic root of 15132991 is about 247.3479173153.

The spelling of 15132991 in words is "fifteen million, one hundred thirty-two thousand, nine hundred ninety-one".