2117872778 has 8 divisors (see below), whose sum is σ = 3630639072. Its totient is φ = 907659756.

The previous prime is 2117872759. The next prime is 2117872817. The reversal of 2117872778 is 8772787112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75638300 + ... + 75638327.

It is an arithmetic number, because the mean of its divisors is an integer number (453829884).

Almost surely, 2^2117872778 is an apocalyptic number.

2117872778 is a deficient number, since it is larger than the sum of its proper divisors (1512766294).

2117872778 is a wasteful number, since it uses less digits than its factorization.

2117872778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151276636.

The product of its digits is 614656, while the sum is 50.

The square root of 2117872778 is about 46020.3517804895. The cubic root of 2117872778 is about 1284.2018446251.

The spelling of 2117872778 in words is "two billion, one hundred seventeen million, eight hundred seventy-two thousand, seven hundred seventy-eight".