669491225 has 12 divisors (see below), whose sum is σ = 894028716. Its totient is φ = 494393280.

The previous prime is 669491203. The next prime is 669491227. The reversal of 669491225 is 522194966.

669491225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 252555664 + 416935561 = 15892^2 + 20419^2 .

It is not a de Polignac number, because 669491225 - 2²⁴ = 652714009 is a prime.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (669491227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1029662 + ... + 1030311.

It is an arithmetic number, because the mean of its divisors is an integer number (74502393).

Almost surely, 2^669491225 is an apocalyptic number.

669491225 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

669491225 is a deficient number, since it is larger than the sum of its proper divisors (224537491).

669491225 is a wasteful number, since it uses less digits than its factorization.

669491225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2059996 (or 2059991 counting only the distinct ones).

The product of its digits is 233280, while the sum is 44.

The square root of 669491225 is about 25874.5284981195. The cubic root of 669491225 is about 874.8124659321.

The spelling of 669491225 in words is "six hundred sixty-nine million, four hundred ninety-one thousand, two hundred twenty-five".