15777776810961 has 24 divisors (see below), whose sum is σ = 24862952936640. Its totient is φ = 9561903746400.

The previous prime is 15777776810927. The next prime is 15777776810977. The reversal of 15777776810961 is 16901867777751.

It is a happy number.

15777776810961 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 15777776810961 - 2⁹ = 15777776810449 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 15777776810961.

It is not an unprimeable number, because it can be changed into a prime (15777776830961) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 730810 + ... + 5664771.

It is an arithmetic number, because the mean of its divisors is an integer number (1035956372360).

Almost surely, 2^{15777776810961} is an apocalyptic number.

15777776810961 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15777776810961 is a deficient number, since it is larger than the sum of its proper divisors (9085176125679).

15777776810961 is a wasteful number, since it uses less digits than its factorization.

15777776810961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6420517 (or 6420514 counting only the distinct ones).

The product of its (nonzero) digits is 217818720, while the sum is 72.

The spelling of 15777776810961 in words is "fifteen trillion, seven hundred seventy-seven billion, seven hundred seventy-six million, eight hundred ten thousand, nine hundred sixty-one".