71447777771 has 4 divisors (see below), whose sum is σ = 71449610232. Its totient is φ = 71445945312.

The previous prime is 71447777743. The next prime is 71447777789. The reversal of 71447777771 is 17777774417.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 71447777771 - 2²² = 71443583467 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 71447777771.

It is not an unprimeable number, because it can be changed into a prime (71447777171) 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, 856445 + ... + 936158.

It is an arithmetic number, because the mean of its divisors is an integer number (17862402558).

Almost surely, 2^71447777771 is an apocalyptic number.

71447777771 is a deficient number, since it is larger than the sum of its proper divisors (1832461).

71447777771 is a wasteful number, since it uses less digits than its factorization.

71447777771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1832460.

The product of its digits is 13176688, while the sum is 59.

The spelling of 71447777771 in words is "seventy-one billion, four hundred forty-seven million, seven hundred seventy-seven thousand, seven hundred seventy-one".