851984155979 has 4 divisors (see below), whose sum is σ = 929437261080. Its totient is φ = 774531050880.

The previous prime is 851984155889. The next prime is 851984155999. The reversal of 851984155979 is 979551489158.

851984155979 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 851984155979 - 2²⁰ = 851983107403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (851984155999) 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, 38726552534 + ... + 38726552555.

It is an arithmetic number, because the mean of its divisors is an integer number (232359315270).

Almost surely, 2^851984155979 is an apocalyptic number.

851984155979 is a deficient number, since it is larger than the sum of its proper divisors (77453105101).

851984155979 is a wasteful number, since it uses less digits than its factorization.

851984155979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77453105100.

The product of its digits is 163296000, while the sum is 71.

The spelling of 851984155979 in words is "eight hundred fifty-one billion, nine hundred eighty-four million, one hundred fifty-five thousand, nine hundred seventy-nine".