1261715904 has 42 divisors (see below), whose sum is σ = 3616482480. Its totient is φ = 420571776.

The previous prime is 1261715879. The next prime is 1261715921. The reversal of 1261715904 is 4095171621.

1261715904 is a `hidden beast` number, since 1 + 2 + 61 + 7 + 1 + 590 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1094664 + ... + 1095815.

Almost surely, 2^1261715904 is an apocalyptic number.

It is an amenable number.

1261715904 is an abundant number, since it is smaller than the sum of its proper divisors (2354766576).

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

1261715904 is a wasteful number, since it uses less digits than its factorization.

1261715904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2190497 (or 2190484 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 1261715904 is about 35520.6405347651. The cubic root of 1261715904 is about 1080.5723715017.

The spelling of 1261715904 in words is "one billion, two hundred sixty-one million, seven hundred fifteen thousand, nine hundred four".