15661161 has 16 divisors (see below), whose sum is σ = 23435520. Its totient is φ = 10335600.

The previous prime is 15661153. The next prime is 15661193. The reversal of 15661161 is 16116651.

It is not a de Polignac number, because 15661161 - 2³ = 15661153 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15661141) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145 + ... + 5598.

It is an arithmetic number, because the mean of its divisors is an integer number (1464720).

Almost surely, 2^15661161 is an apocalyptic number.

It is an amenable number.

15661161 is a deficient number, since it is larger than the sum of its proper divisors (7774359).

15661161 is a wasteful number, since it uses less digits than its factorization.

15661161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5853 (or 5847 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 15661161 is about 3957.4184767345. The cubic root of 15661161 is about 250.1927100798.

The spelling of 15661161 in words is "fifteen million, six hundred sixty-one thousand, one hundred sixty-one".