641890997 has 8 divisors (see below), whose sum is σ = 700430112. Its totient is φ = 583382800.

The previous prime is 641890993. The next prime is 641891011. The reversal of 641890997 is 799098146.

It is a happy number.

641890997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 641890997 - 2² = 641890993 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 (641890993) 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, 67958 + ... + 76824.

It is an arithmetic number, because the mean of its divisors is an integer number (87553764).

Almost surely, 2^641890997 is an apocalyptic number.

It is an amenable number.

641890997 is a deficient number, since it is larger than the sum of its proper divisors (58539115).

641890997 is a wasteful number, since it uses less digits than its factorization.

641890997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15459.

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

The square root of 641890997 is about 25335.5678247005. The cubic root of 641890997 is about 862.6217976004.

The spelling of 641890997 in words is "six hundred forty-one million, eight hundred ninety thousand, nine hundred ninety-seven".