561055966639 has 16 divisors (see below), whose sum is σ = 662211348480. Its totient is φ = 465166738080.

The previous prime is 561055966637. The next prime is 561055966643. The reversal of 561055966639 is 936669550165.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 561055966639 - 2¹ = 561055966637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561055966637) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175849 + ... + 1073794.

It is an arithmetic number, because the mean of its divisors is an integer number (41388209280).

Almost surely, 2^561055966639 is an apocalyptic number.

561055966639 is a deficient number, since it is larger than the sum of its proper divisors (101155381841).

561055966639 is a wasteful number, since it uses less digits than its factorization.

561055966639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1251750.

The product of its (nonzero) digits is 39366000, while the sum is 61.

The spelling of 561055966639 in words is "five hundred sixty-one billion, fifty-five million, nine hundred sixty-six thousand, six hundred thirty-nine".