641399998 has 8 divisors (see below), whose sum is σ = 966126240. Its totient is φ = 319357920.

The previous prime is 641399981. The next prime is 641399999. The reversal of 641399998 is 899993146.

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

It is a super-2 number, since 2×641399998² = 822787914868800008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641399999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 670443 + ... + 671398.

It is an arithmetic number, because the mean of its divisors is an integer number (120765780).

Almost surely, 2^641399998 is an apocalyptic number.

641399998 is a deficient number, since it is larger than the sum of its proper divisors (324726242).

641399998 is a wasteful number, since it uses less digits than its factorization.

641399998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1342082.

The product of its digits is 3779136, while the sum is 58.

The square root of 641399998 is about 25325.8760559235. The cubic root of 641399998 is about 862.4017942656.

The spelling of 641399998 in words is "six hundred forty-one million, three hundred ninety-nine thousand, nine hundred ninety-eight".