71747979689 has 4 divisors (see below), whose sum is σ = 71895306624. Its totient is φ = 71600652756.

The previous prime is 71747979679. The next prime is 71747979731. The reversal of 71747979689 is 98697974717.

It is a happy number.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71747979689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71747979659) 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, 73662737 + ... + 73663710.

It is an arithmetic number, because the mean of its divisors is an integer number (17973826656).

Almost surely, 2^71747979689 is an apocalyptic number.

It is an amenable number.

71747979689 is a deficient number, since it is larger than the sum of its proper divisors (147326935).

71747979689 is a wasteful number, since it uses less digits than its factorization.

71747979689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147326934.

The product of its digits is 336063168, while the sum is 74.

The spelling of 71747979689 in words is "seventy-one billion, seven hundred forty-seven million, nine hundred seventy-nine thousand, six hundred eighty-nine".