71561663316 has 72 divisors (see below), whose sum is σ = 212516469984. Its totient is φ = 20017247040.

The previous prime is 71561663291. The next prime is 71561663317. The reversal of 71561663316 is 61336616517.

It is a happy number.

71561663316 is a `hidden beast` number, since 7 + 1 + 5 + 6 + 1 + 6 + 633 + 1 + 6 = 666.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71561663317) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6945286 + ... + 6955581.

Almost surely, 2^71561663316 is an apocalyptic number.

It is an amenable number.

71561663316 is an abundant number, since it is smaller than the sum of its proper divisors (140954806668).

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

71561663316 is a wasteful number, since it uses less digits than its factorization.

71561663316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13900901 (or 13900896 counting only the distinct ones).

The product of its digits is 408240, while the sum is 45.

The spelling of 71561663316 in words is "seventy-one billion, five hundred sixty-one million, six hundred sixty-three thousand, three hundred sixteen".