77685881815 has 8 divisors (see below), whose sum is σ = 94981984128. Its totient is φ = 60976088160.

The previous prime is 77685881813. The next prime is 77685881831. The reversal of 77685881815 is 51818858677.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 77685881815 - 2¹ = 77685881813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77685881813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 146576871 + ... + 146577400.

It is an arithmetic number, because the mean of its divisors is an integer number (11872748016).

Almost surely, 2^77685881815 is an apocalyptic number.

77685881815 is a deficient number, since it is larger than the sum of its proper divisors (17296102313).

77685881815 is a wasteful number, since it uses less digits than its factorization.

77685881815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293154329.

The product of its digits is 30105600, while the sum is 64.

The spelling of 77685881815 in words is "seventy-seven billion, six hundred eighty-five million, eight hundred eighty-one thousand, eight hundred fifteen".