15661404366 has 8 divisors (see below), whose sum is σ = 31322808744. Its totient is φ = 5220468120.

The previous prime is 15661404359. The next prime is 15661404371. The reversal of 15661404366 is 66340416651.

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

15661404366 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1305117025 + ... + 1305117036.

It is an arithmetic number, because the mean of its divisors is an integer number (3915351093).

Almost surely, 2^15661404366 is an apocalyptic number.

15661404366 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15661404366 is a wasteful number, since it uses less digits than its factorization.

15661404366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2610234066.

The product of its (nonzero) digits is 311040, while the sum is 42.

The spelling of 15661404366 in words is "fifteen billion, six hundred sixty-one million, four hundred four thousand, three hundred sixty-six".