641820739 has 8 divisors (see below), whose sum is σ = 733766240. Its totient is φ = 549939456.

The previous prime is 641820733. The next prime is 641820743. The reversal of 641820739 is 937028146.

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 641820739 - 2³ = 641820731 is a prime.

It is a super-2 number, since 2×641820739² = 823867722021012242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (641820731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7717 + ... + 36649.

It is an arithmetic number, because the mean of its divisors is an integer number (91720780).

Almost surely, 2^641820739 is an apocalyptic number.

641820739 is a deficient number, since it is larger than the sum of its proper divisors (91945501).

641820739 is a wasteful number, since it uses less digits than its factorization.

641820739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32109.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 641820739 is about 25334.1812380033. The cubic root of 641820739 is about 862.5903237760.

The spelling of 641820739 in words is "six hundred forty-one million, eight hundred twenty thousand, seven hundred thirty-nine".