71642605591 has 4 divisors (see below), whose sum is σ = 71648895384. Its totient is φ = 71636315800.

The previous prime is 71642605577. The next prime is 71642605603. The reversal of 71642605591 is 19550624617.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19550624617 = 19 ⋅1028980243.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71642605591 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 (71642605561) 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, 3127780 + ... + 3150601.

It is an arithmetic number, because the mean of its divisors is an integer number (17912223846).

Almost surely, 2^71642605591 is an apocalyptic number.

71642605591 is a deficient number, since it is larger than the sum of its proper divisors (6289793).

71642605591 is a wasteful number, since it uses less digits than its factorization.

71642605591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6289792.

The product of its (nonzero) digits is 453600, while the sum is 46.

The spelling of 71642605591 in words is "seventy-one billion, six hundred forty-two million, six hundred five thousand, five hundred ninety-one".