666490725 has 36 divisors (see below), whose sum is σ = 1196503776. Its totient is φ = 354644640.

The previous prime is 666490723. The next prime is 666490733. The reversal of 666490725 is 527094666.

It is not a de Polignac number, because 666490725 - 2¹ = 666490723 is a prime.

It is a super-2 number, since 2×666490725² = 888419773022051250, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666490723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 101904 + ... + 108246.

It is an arithmetic number, because the mean of its divisors is an integer number (33236216).

Almost surely, 2^666490725 is an apocalyptic number.

It is an amenable number.

666490725 is a deficient number, since it is larger than the sum of its proper divisors (530013051).

666490725 is a wasteful number, since it uses less digits than its factorization.

666490725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6826 (or 6818 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 45.

The square root of 666490725 is about 25816.4816541681. The cubic root of 666490725 is about 873.5036083733.

The spelling of 666490725 in words is "six hundred sixty-six million, four hundred ninety thousand, seven hundred twenty-five".