1561231704 has 64 divisors (see below), whose sum is σ = 4045075200. Its totient is φ = 501544064.

The previous prime is 1561231699. The next prime is 1561231717. The reversal of 1561231704 is 4071321651.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 448579 + ... + 452045.

It is an arithmetic number, because the mean of its divisors is an integer number (63204300).

Almost surely, 2^1561231704 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1561231704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2022537600).

1561231704 is an abundant number, since it is smaller than the sum of its proper divisors (2483843496).

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

1561231704 is a wasteful number, since it uses less digits than its factorization.

1561231704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4152 (or 4148 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 1561231704 is about 39512.4246788273. The cubic root of 1561231704 is about 1160.0831549584.

The spelling of 1561231704 in words is "one billion, five hundred sixty-one million, two hundred thirty-one thousand, seven hundred four".