15665939655 has 16 divisors (see below), whose sum is σ = 25598813184. Its totient is φ = 8177397920.

The previous prime is 15665939633. The next prime is 15665939669. The reversal of 15665939655 is 55693956651.

15665939655 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 15665939655 - 2¹⁷ = 15665808583 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11109891 + ... + 11111300.

It is an arithmetic number, because the mean of its divisors is an integer number (1599925824).

Almost surely, 2^15665939655 is an apocalyptic number.

15665939655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

15665939655 is a deficient number, since it is larger than the sum of its proper divisors (9932873529).

15665939655 is a wasteful number, since it uses less digits than its factorization.

15665939655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22221246.

The product of its digits is 32805000, while the sum is 60.

The spelling of 15665939655 in words is "fifteen billion, six hundred sixty-five million, nine hundred thirty-nine thousand, six hundred fifty-five".