664172527 has 4 divisors (see below), whose sum is σ = 668149776. Its totient is φ = 660195280.

The previous prime is 664172501. The next prime is 664172549. The reversal of 664172527 is 725271466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 664172527 - 2¹⁹ = 663648239 is a prime.

It is a super-2 number, since 2×664172527² = 882250291243131458, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664172527.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664172827) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1988374 + ... + 1988707.

It is an arithmetic number, because the mean of its divisors is an integer number (167037444).

Almost surely, 2^664172527 is an apocalyptic number.

664172527 is a deficient number, since it is larger than the sum of its proper divisors (3977249).

664172527 is a wasteful number, since it uses less digits than its factorization.

664172527 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3977248.

The product of its digits is 141120, while the sum is 40.

The square root of 664172527 is about 25771.5449090659. The cubic root of 664172527 is about 872.4896874833.

The spelling of 664172527 in words is "six hundred sixty-four million, one hundred seventy-two thousand, five hundred twenty-seven".