1561795956 has 72 divisors (see below), whose sum is σ = 4708040064. Its totient is φ = 426824640.

The previous prime is 1561795931. The next prime is 1561795973. The reversal of 1561795956 is 6595971651.

1561795956 is a `hidden beast` number, since 1 + 561 + 79 + 5 + 9 + 5 + 6 = 666.

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 23 ways as a sum of consecutive naturals, for example, 128935 + ... + 140526.

Almost surely, 2^1561795956 is an apocalyptic number.

It is an amenable number.

1561795956 is an abundant number, since it is smaller than the sum of its proper divisors (3146244108).

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

1561795956 is a wasteful number, since it uses less digits than its factorization.

1561795956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269501 (or 269496 counting only the distinct ones).

The product of its digits is 2551500, while the sum is 54.

The square root of 1561795956 is about 39519.5642182451. The cubic root of 1561795956 is about 1160.2228951384. Note that the first 3 decimals are identical.

The spelling of 1561795956 in words is "one billion, five hundred sixty-one million, seven hundred ninety-five thousand, nine hundred fifty-six".