664189837 has 16 divisors (see below), whose sum is σ = 705376512. Its totient is φ = 624131200.

The previous prime is 664189831. The next prime is 664189861. The reversal of 664189837 is 738981466.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 664189837 - 2³ = 664189829 is a prime.

It is a super-2 number, since 2×664189837² = 882296279148173138, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664189831) 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, 317208 + ... + 319294.

It is an arithmetic number, because the mean of its divisors is an integer number (44086032).

Almost surely, 2^664189837 is an apocalyptic number.

It is an amenable number.

664189837 is a deficient number, since it is larger than the sum of its proper divisors (41186675).

664189837 is a wasteful number, since it uses less digits than its factorization.

664189837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2348.

The product of its digits is 1741824, while the sum is 52.

The square root of 664189837 is about 25771.8807423905. The cubic root of 664189837 is about 872.4972671732.

The spelling of 664189837 in words is "six hundred sixty-four million, one hundred eighty-nine thousand, eight hundred thirty-seven".