2164159778 has 36 divisors (see below), whose sum is σ = 3611919570. Its totient is φ = 971794560.

The previous prime is 2164159763. The next prime is 2164159783. The reversal of 2164159778 is 8779514612.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 692900329 + 1471259449 = 26323^2 + 38357^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1916318 + ... + 1917446.

Almost surely, 2^2164159778 is an apocalyptic number.

2164159778 is a deficient number, since it is larger than the sum of its proper divisors (1447759792).

2164159778 is a wasteful number, since it uses less digits than its factorization.

2164159778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1331 (or 1231 counting only the distinct ones).

The product of its digits is 846720, while the sum is 50.

The square root of 2164159778 is about 46520.5307149435. The cubic root of 2164159778 is about 1293.4900939374.

The spelling of 2164159778 in words is "two billion, one hundred sixty-four million, one hundred fifty-nine thousand, seven hundred seventy-eight".