261715390416 has 40 divisors (see below), whose sum is σ = 751220103360. Its totient is φ = 87238463328.

The previous prime is 261715390399. The next prime is 261715390421. The reversal of 261715390416 is 614093517162.

261715390416 is a `hidden beast` number, since 2 + 6 + 1 + 71 + 539 + 0 + 41 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 302910900 + ... + 302911763.

It is an arithmetic number, because the mean of its divisors is an integer number (18780502584).

Almost surely, 2^261715390416 is an apocalyptic number.

It is an amenable number.

261715390416 is an abundant number, since it is smaller than the sum of its proper divisors (489504712944).

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

261715390416 is a wasteful number, since it uses less digits than its factorization.

261715390416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 605822680 (or 605822668 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The spelling of 261715390416 in words is "two hundred sixty-one billion, seven hundred fifteen million, three hundred ninety thousand, four hundred sixteen".