1664706918 has 16 divisors (see below), whose sum is σ = 3805044480. Its totient is φ = 475630536.

The previous prime is 1664706863. The next prime is 1664706931. The reversal of 1664706918 is 8196074661.

It is a happy number.

It is a super-3 number, since 3×1664706918³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19817898 + ... + 19817981.

It is an arithmetic number, because the mean of its divisors is an integer number (237815280).

Almost surely, 2^1664706918 is an apocalyptic number.

1664706918 is an abundant number, since it is smaller than the sum of its proper divisors (2140337562).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1664706918 is a wasteful number, since it uses less digits than its factorization.

1664706918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39635891.

The product of its (nonzero) digits is 435456, while the sum is 48.

The square root of 1664706918 is about 40800.8200652879. The cubic root of 1664706918 is about 1185.1662114415.

The spelling of 1664706918 in words is "one billion, six hundred sixty-four million, seven hundred six thousand, nine hundred eighteen".