71976977781 has 16 divisors (see below), whose sum is σ = 97330234560. Its totient is φ = 47304812160.

The previous prime is 71976977771. The next prime is 71976977887. The reversal of 71976977781 is 18777967917.

It is not a de Polignac number, because 71976977781 - 2³⁰ = 70903235957 is a prime.

It is a super-2 number, since 2×71976977781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71976977741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 389575 + ... + 543803.

It is an arithmetic number, because the mean of its divisors is an integer number (6083139660).

Almost surely, 2^71976977781 is an apocalyptic number.

It is an amenable number.

71976977781 is a deficient number, since it is larger than the sum of its proper divisors (25353256779).

71976977781 is a wasteful number, since it uses less digits than its factorization.

71976977781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156436.

The product of its digits is 65345616, while the sum is 69.

The spelling of 71976977781 in words is "seventy-one billion, nine hundred seventy-six million, nine hundred seventy-seven thousand, seven hundred eighty-one".