71709291561 has 4 divisors (see below), whose sum is σ = 95612388752. Its totient is φ = 47806194372.

The previous prime is 71709291527. The next prime is 71709291649. The reversal of 71709291561 is 16519290717.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 71709291561 - 2⁶ = 71709291497 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71709291561.

It is not an unprimeable number, because it can be changed into a prime (71709292561) 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, 11951548591 + ... + 11951548596.

It is an arithmetic number, because the mean of its divisors is an integer number (23903097188).

Almost surely, 2^71709291561 is an apocalyptic number.

It is an amenable number.

71709291561 is a deficient number, since it is larger than the sum of its proper divisors (23903097191).

71709291561 is a wasteful number, since it uses less digits than its factorization.

71709291561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23903097190.

The product of its (nonzero) digits is 238140, while the sum is 48.

The spelling of 71709291561 in words is "seventy-one billion, seven hundred nine million, two hundred ninety-one thousand, five hundred sixty-one".