71636849861 has 4 divisors (see below), whose sum is σ = 75407210400. Its totient is φ = 67866489324.

The previous prime is 71636849833. The next prime is 71636849897. The reversal of 71636849861 is 16894863617.

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, and also an emirpimes, since its reverse is a distinct semiprime: 16894863617 = 67751 ⋅249367.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71636849861 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 71636849861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71632849861) 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, 1885180241 + ... + 1885180278.

It is an arithmetic number, because the mean of its divisors is an integer number (18851802600).

Almost surely, 2^71636849861 is an apocalyptic number.

It is an amenable number.

71636849861 is a deficient number, since it is larger than the sum of its proper divisors (3770360539).

71636849861 is a wasteful number, since it uses less digits than its factorization.

71636849861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3770360538.

The product of its digits is 10450944, while the sum is 59.

The spelling of 71636849861 in words is "seventy-one billion, six hundred thirty-six million, eight hundred forty-nine thousand, eight hundred sixty-one".