639544297 has 8 divisors (see below), whose sum is σ = 750662336. Its totient is φ = 533364912.

The previous prime is 639544277. The next prime is 639544307. The reversal of 639544297 is 792445936.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-639544297 is a prime.

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 639544297.

It is not an unprimeable number, because it can be changed into a prime (639544277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1234383 + ... + 1234900.

It is an arithmetic number, because the mean of its divisors is an integer number (93832792).

Almost surely, 2^639544297 is an apocalyptic number.

It is an amenable number.

639544297 is a deficient number, since it is larger than the sum of its proper divisors (111118039).

639544297 is a wasteful number, since it uses less digits than its factorization.

639544297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2469327.

The product of its digits is 1632960, while the sum is 49.

The square root of 639544297 is about 25289.2130561629. The cubic root of 639544297 is about 861.5692894575.

The spelling of 639544297 in words is "six hundred thirty-nine million, five hundred forty-four thousand, two hundred ninety-seven".