1856665994 has 12 divisors (see below), whose sum is σ = 2860840374. Its totient is φ = 903062592.

The previous prime is 1856665991. The next prime is 1856666027. The reversal of 1856665994 is 4995666581.

It can be written as a sum of positive squares in 3 ways, for example, as 1788190369 + 68475625 = 42287^2 + 8275^2 .

It is a super-2 number, since 2×1856665994² = 6894417226552016072, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1856665991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 368162 + ... + 373170.

Almost surely, 2^1856665994 is an apocalyptic number.

1856665994 is a deficient number, since it is larger than the sum of its proper divisors (1004174380).

1856665994 is an frugal number, since it uses more digits than its factorization.

1856665994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10057 (or 5048 counting only the distinct ones).

The product of its digits is 13996800, while the sum is 59.

The square root of 1856665994 is about 43089.0472626165. The cubic root of 1856665994 is about 1229.0737058404.

The spelling of 1856665994 in words is "one billion, eight hundred fifty-six million, six hundred sixty-five thousand, nine hundred ninety-four".