15963661 has 12 divisors (see below), whose sum is σ = 18756192. Its totient is φ = 13546008.

The previous prime is 15963643. The next prime is 15963709. The reversal of 15963661 is 16636951.

It is not a de Polignac number, because 15963661 - 2⁹ = 15963149 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 15963661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15963611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3466 + ... + 6628.

It is an arithmetic number, because the mean of its divisors is an integer number (1563016).

Almost surely, 2^15963661 is an apocalyptic number.

It is an amenable number.

15963661 is a deficient number, since it is larger than the sum of its proper divisors (2792531).

15963661 is a wasteful number, since it uses less digits than its factorization.

15963661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3280 (or 3273 counting only the distinct ones).

The product of its digits is 29160, while the sum is 37.

The square root of 15963661 is about 3995.4550429206. The cubic root of 15963661 is about 251.7932975774.

The spelling of 15963661 in words is "fifteen million, nine hundred sixty-three thousand, six hundred sixty-one".