1561641631544 has 16 divisors (see below), whose sum is σ = 2928091750200. Its totient is φ = 780817164832.

The previous prime is 1561641631507. The next prime is 1561641631549. The reversal of 1561641631544 is 4451361461651.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561641631549) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2451134 + ... + 3021810.

Almost surely, 2^{1561641631544} is an apocalyptic number.

It is an amenable number.

1561641631544 is a deficient number, since it is larger than the sum of its proper divisors (1366450118656).

1561641631544 is a wasteful number, since it uses less digits than its factorization.

1561641631544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 912742 (or 912738 counting only the distinct ones).

The product of its digits is 1036800, while the sum is 47.

The spelling of 1561641631544 in words is "one trillion, five hundred sixty-one billion, six hundred forty-one million, six hundred thirty-one thousand, five hundred forty-four".