1561772408 has 16 divisors (see below), whose sum is σ = 3346655280. Its totient is φ = 669331008.

The previous prime is 1561772339. The next prime is 1561772411. The reversal of 1561772408 is 8042771651.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13944341 + ... + 13944452.

It is an arithmetic number, because the mean of its divisors is an integer number (209165955).

Almost surely, 2^1561772408 is an apocalyptic number.

It is an amenable number.

1561772408 is an abundant number, since it is smaller than the sum of its proper divisors (1784882872).

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

1561772408 is a wasteful number, since it uses less digits than its factorization.

1561772408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27888806 (or 27888802 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 41.

The square root of 1561772408 is about 39519.2662887357. The cubic root of 1561772408 is about 1160.2170640169.

The spelling of 1561772408 in words is "one billion, five hundred sixty-one million, seven hundred seventy-two thousand, four hundred eight".