1561039404 has 24 divisors (see below), whose sum is σ = 3674662320. Its totient is φ = 515741184.

The previous prime is 1561039397. The next prime is 1561039421. The reversal of 1561039404 is 4049301651.

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, 574249 + ... + 576960.

It is an arithmetic number, because the mean of its divisors is an integer number (153110930).

Almost surely, 2^1561039404 is an apocalyptic number.

It is an amenable number.

1561039404 is an abundant number, since it is smaller than the sum of its proper divisors (2113622916).

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

1561039404 is a wasteful number, since it uses less digits than its factorization.

1561039404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1151329 (or 1151327 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 1561039404 is about 39509.9911921023. The cubic root of 1561039404 is about 1160.0355230897.

The spelling of 1561039404 in words is "one billion, five hundred sixty-one million, thirty-nine thousand, four hundred four".