71561780056972 has 6 divisors (see below), whose sum is σ = 125233115099708. Its totient is φ = 35780890028484.

The previous prime is 71561780056967. The next prime is 71561780056973. The reversal of 71561780056972 is 27965008716517.

It is not an unprimeable number, because it can be changed into a prime (71561780056973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8945222507118 + ... + 8945222507125.

Almost surely, 2^{71561780056972} is an apocalyptic number.

It is an amenable number.

71561780056972 is a deficient number, since it is larger than the sum of its proper divisors (53671335042736).

71561780056972 is a wasteful number, since it uses less digits than its factorization.

71561780056972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17890445014247 (or 17890445014245 counting only the distinct ones).

The product of its (nonzero) digits is 44452800, while the sum is 64.

The spelling of 71561780056972 in words is "seventy-one trillion, five hundred sixty-one billion, seven hundred eighty million, fifty-six thousand, nine hundred seventy-two".