77381685251 has 4 divisors (see below), whose sum is σ = 83334122592. Its totient is φ = 71429247912.

The previous prime is 77381685247. The next prime is 77381685253. The reversal of 77381685251 is 15258618377.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15258618377 = 733 ⋅20816669.

It is a cyclic number.

It is not a de Polignac number, because 77381685251 - 2² = 77381685247 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77381685193 and 77381685202.

It is not an unprimeable number, because it can be changed into a prime (77381685253) 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, 2976218651 + ... + 2976218676.

It is an arithmetic number, because the mean of its divisors is an integer number (20833530648).

Almost surely, 2^77381685251 is an apocalyptic number.

77381685251 is a deficient number, since it is larger than the sum of its proper divisors (5952437341).

77381685251 is a wasteful number, since it uses less digits than its factorization.

77381685251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5952437340.

The product of its digits is 2822400, while the sum is 53.

The spelling of 77381685251 in words is "seventy-seven billion, three hundred eighty-one million, six hundred eighty-five thousand, two hundred fifty-one".