77953886809 has 4 divisors (see below), whose sum is σ = 79424714916. Its totient is φ = 76483058704.

The previous prime is 77953886807. The next prime is 77953886863. The reversal of 77953886809 is 90868835977.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 58275408409 + 19678478400 = 241403^2 + 140280^2 .

It is a cyclic number.

It is not a de Polignac number, because 77953886809 - 2¹ = 77953886807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77953886807) 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, 735413974 + ... + 735414079.

It is an arithmetic number, because the mean of its divisors is an integer number (19856178729).

Almost surely, 2^77953886809 is an apocalyptic number.

It is an amenable number.

77953886809 is a deficient number, since it is larger than the sum of its proper divisors (1470828107).

77953886809 is a wasteful number, since it uses less digits than its factorization.

77953886809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1470828106.

The product of its (nonzero) digits is 182891520, while the sum is 70.

The spelling of 77953886809 in words is "seventy-seven billion, nine hundred fifty-three million, eight hundred eighty-six thousand, eight hundred nine".