639380898 has 32 divisors (see below), whose sum is σ = 1530144000. Its totient is φ = 196732368.

The previous prime is 639380873. The next prime is 639380899. The reversal of 639380898 is 898083936.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (639380899) 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, 454698 + ... + 456101.

It is an arithmetic number, because the mean of its divisors is an integer number (47817000).

Almost surely, 2^639380898 is an apocalyptic number.

639380898 is an abundant number, since it is smaller than the sum of its proper divisors (890763102).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639380898 is a wasteful number, since it uses less digits than its factorization.

639380898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 910823 (or 910817 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The square root of 639380898 is about 25285.9822431323. The cubic root of 639380898 is about 861.4959082744.

The spelling of 639380898 in words is "six hundred thirty-nine million, three hundred eighty thousand, eight hundred ninety-eight".