15591961 has 8 divisors (see below), whose sum is σ = 19439424. Its totient is φ = 12149520.

The previous prime is 15591893. The next prime is 15591973. The reversal of 15591961 is 16919551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 15591961 - 2⁹ = 15591449 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 15591961.

It is not an unprimeable number, because it can be changed into a prime (15591061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101170 + ... + 101323.

It is an arithmetic number, because the mean of its divisors is an integer number (2429928).

Almost surely, 2^15591961 is an apocalyptic number.

15591961 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15591961 is a deficient number, since it is larger than the sum of its proper divisors (3847463).

15591961 is a wasteful number, since it uses less digits than its factorization.

15591961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202511.

The product of its digits is 12150, while the sum is 37.

The square root of 15591961 is about 3948.6657240136. The cubic root of 15591961 is about 249.8236676569.

The spelling of 15591961 in words is "fifteen million, five hundred ninety-one thousand, nine hundred sixty-one".