638984797 has 16 divisors (see below), whose sum is σ = 741379392. Its totient is φ = 544280320.

The previous prime is 638984791. The next prime is 638984813. The reversal of 638984797 is 797489836.

It is a cyclic number.

It is not a de Polignac number, because 638984797 - 2³ = 638984789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638984791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34923 + ... + 49975.

It is an arithmetic number, because the mean of its divisors is an integer number (46336212).

Almost surely, 2^638984797 is an apocalyptic number.

It is an amenable number.

638984797 is a deficient number, since it is larger than the sum of its proper divisors (102394595).

638984797 is a wasteful number, since it uses less digits than its factorization.

638984797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15308.

The product of its digits is 18289152, while the sum is 61.

The square root of 638984797 is about 25278.1486070479. The cubic root of 638984797 is about 861.3179705835.

The spelling of 638984797 in words is "six hundred thirty-eight million, nine hundred eighty-four thousand, seven hundred ninety-seven".