641998079 has 8 divisors (see below), whose sum is σ = 647786400. Its totient is φ = 636235776.

The previous prime is 641998033. The next prime is 641998109. The reversal of 641998079 is 970899146.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 641998079 - 2⁸ = 641997823 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 641998079.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641998009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44867 + ... + 57419.

It is an arithmetic number, because the mean of its divisors is an integer number (80973300).

Almost surely, 2^641998079 is an apocalyptic number.

641998079 is a deficient number, since it is larger than the sum of its proper divisors (5788321).

641998079 is a wasteful number, since it uses less digits than its factorization.

641998079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13009.

The product of its (nonzero) digits is 979776, while the sum is 53.

The square root of 641998079 is about 25337.6810107002. The cubic root of 641998079 is about 862.6697632372.

The spelling of 641998079 in words is "six hundred forty-one million, nine hundred ninety-eight thousand, seventy-nine".