77141807781 has 4 divisors (see below), whose sum is σ = 102855743712. Its totient is φ = 51427871852.

The previous prime is 77141807759. The next prime is 77141807791. The reversal of 77141807781 is 18770814177.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18770814177 = 3 ⋅6256938059.

It is a cyclic number.

It is not a de Polignac number, because 77141807781 - 2⁷ = 77141807653 is a prime.

It is a super-2 number, since 2×77141807781² (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 (77141807791) 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, 12856967961 + ... + 12856967966.

It is an arithmetic number, because the mean of its divisors is an integer number (25713935928).

Almost surely, 2^77141807781 is an apocalyptic number.

It is an amenable number.

77141807781 is a deficient number, since it is larger than the sum of its proper divisors (25713935931).

77141807781 is a wasteful number, since it uses less digits than its factorization.

77141807781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25713935930.

The product of its (nonzero) digits is 614656, while the sum is 51.

The spelling of 77141807781 in words is "seventy-seven billion, one hundred forty-one million, eight hundred seven thousand, seven hundred eighty-one".