641989597 has 4 divisors (see below), whose sum is σ = 651031776. Its totient is φ = 632947420.

The previous prime is 641989589. The next prime is 641989609. The reversal of 641989597 is 795989146.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 795989146 = 2 ⋅397994573.

It is a cyclic number.

It is not a de Polignac number, because 641989597 - 2³ = 641989589 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 (641989507) 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, 4520983 + ... + 4521124.

It is an arithmetic number, because the mean of its divisors is an integer number (162757944).

Almost surely, 2^641989597 is an apocalyptic number.

It is an amenable number.

641989597 is a deficient number, since it is larger than the sum of its proper divisors (9042179).

641989597 is an equidigital number, since it uses as much as digits as its factorization.

641989597 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9042178.

The product of its digits is 4898880, while the sum is 58.

The square root of 641989597 is about 25337.5136309781. The cubic root of 641989597 is about 862.6659640580.

The spelling of 641989597 in words is "six hundred forty-one million, nine hundred eighty-nine thousand, five hundred ninety-seven".