561779957956 has 24 divisors (see below), whose sum is σ = 1124008941440. Its totient is φ = 240666619392.

The previous prime is 561779957939. The next prime is 561779957957. The reversal of 561779957956 is 659759977165.

It is a super-2 number, since 2×561779957956² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (561779957957) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3937821 + ... + 4077988.

Almost surely, 2^561779957956 is an apocalyptic number.

It is an amenable number.

561779957956 is an abundant number, since it is smaller than the sum of its proper divisors (562228983484).

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

561779957956 is a wasteful number, since it uses less digits than its factorization.

561779957956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8018323 (or 8018321 counting only the distinct ones).

The product of its digits is 1125211500, while the sum is 76.

The spelling of 561779957956 in words is "five hundred sixty-one billion, seven hundred seventy-nine million, nine hundred fifty-seven thousand, nine hundred fifty-six".