1664663880 has 64 divisors (see below), whose sum is σ = 5447995200. Its totient is φ = 403554560.

The previous prime is 1664663873. The next prime is 1664663881. The reversal of 1664663880 is 883664661.

It is a super-2 number, since 2×1664663880² = 5542211666753308800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1664663881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 629235 + ... + 631874.

It is an arithmetic number, because the mean of its divisors is an integer number (85124925).

Almost surely, 2^1664663880 is an apocalyptic number.

1664663880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1664663880 is an abundant number, since it is smaller than the sum of its proper divisors (3783331320).

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

1664663880 is a wasteful number, since it uses less digits than its factorization.

1664663880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1261134 (or 1261130 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 48.

The square root of 1664663880 is about 40800.2926460093. The cubic root of 1664663880 is about 1185.1559979073.

The spelling of 1664663880 in words is "one billion, six hundred sixty-four million, six hundred sixty-three thousand, eight hundred eighty".