77999951801 has 4 divisors (see below), whose sum is σ = 78408328704. Its totient is φ = 77591574900.

The previous prime is 77999951717. The next prime is 77999951833. The reversal of 77999951801 is 10815999977.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77999951801 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (77999951401) 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, 204188165 + ... + 204188546.

It is an arithmetic number, because the mean of its divisors is an integer number (19602082176).

Almost surely, 2^77999951801 is an apocalyptic number.

It is an amenable number.

77999951801 is a deficient number, since it is larger than the sum of its proper divisors (408376903).

77999951801 is a wasteful number, since it uses less digits than its factorization.

77999951801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408376902.

The product of its (nonzero) digits is 12859560, while the sum is 65.

The spelling of 77999951801 in words is "seventy-seven billion, nine hundred ninety-nine million, nine hundred fifty-one thousand, eight hundred one".