1561617936 has 60 divisors (see below), whose sum is σ = 4560386688. Its totient is φ = 497906112.

The previous prime is 1561617931. The next prime is 1561617947. The reversal of 1561617936 is 6397161651.

1561617936 is a `hidden beast` number, since 15 + 616 + 17 + 9 + 3 + 6 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 1561617891 and 1561617900.

It is not an unprimeable number, because it can be changed into a prime (1561617931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 232440 + ... + 239063.

Almost surely, 2^1561617936 is an apocalyptic number.

1561617936 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1561617936 is an abundant number, since it is smaller than the sum of its proper divisors (2998768752).

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

1561617936 is a wasteful number, since it uses less digits than its factorization.

1561617936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 471540 (or 471531 counting only the distinct ones).

The product of its digits is 204120, while the sum is 45.

The square root of 1561617936 is about 39517.3118518960. The cubic root of 1561617936 is about 1160.1788111194.

The spelling of 1561617936 in words is "one billion, five hundred sixty-one million, six hundred seventeen thousand, nine hundred thirty-six".