77939779542 has 16 divisors (see below), whose sum is σ = 155894300352. Its totient is φ = 25977469640.

The previous prime is 77939779537. The next prime is 77939779607. The reversal of 77939779542 is 24597793977.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 544884 + ... + 672887.

It is an arithmetic number, because the mean of its divisors is an integer number (9743393772).

Almost surely, 2^77939779542 is an apocalyptic number.

77939779542 is an abundant number, since it is smaller than the sum of its proper divisors (77954520810).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77939779542 is a wasteful number, since it uses less digits than its factorization.

77939779542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1228443.

The product of its digits is 210039480, while the sum is 69.

The spelling of 77939779542 in words is "seventy-seven billion, nine hundred thirty-nine million, seven hundred seventy-nine thousand, five hundred forty-two".