1561656504 has 16 divisors (see below), whose sum is σ = 3904141320. Its totient is φ = 520552160.

The previous prime is 1561656487. The next prime is 1561656517. The reversal of 1561656504 is 4056561651.

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 3 ways as a sum of consecutive naturals, for example, 32534487 + ... + 32534534.

Almost surely, 2^1561656504 is an apocalyptic number.

It is an amenable number.

1561656504 is an abundant number, since it is smaller than the sum of its proper divisors (2342484816).

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

1561656504 is a wasteful number, since it uses less digits than its factorization.

1561656504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65069030 (or 65069026 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 39.

The square root of 1561656504 is about 39517.7998375416. The cubic root of 1561656504 is about 1160.1883621982.

The spelling of 1561656504 in words is "one billion, five hundred sixty-one million, six hundred fifty-six thousand, five hundred four".