1665292864 has 21 divisors (see below), whose sum is σ = 3305213481. Its totient is φ = 832483200.

The previous prime is 1665292801. The next prime is 1665292879. The reversal of 1665292864 is 4682925661.

The square root of 1665292864 is 40808.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 652864 + 1664640000 = 808^2 + 40800^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 323914 + ... + 329014.

Almost surely, 2^1665292864 is an apocalyptic number.

1665292864 is the 40808-th square number.

It is an amenable number.

1665292864 is a deficient number, since it is larger than the sum of its proper divisors (1639920617).

1665292864 is an frugal number, since it uses more digits than its factorization.

1665292864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10214 (or 5103 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 49.

The cubic root of 1665292864 is about 1185.3052473146.

Multiplying 1665292864 by its sum of digits (49), we get a square (81599350336 = 285656²).

The spelling of 1665292864 in words is "one billion, six hundred sixty-five million, two hundred ninety-two thousand, eight hundred sixty-four".