641672820847 has 2 divisors, whose sum is σ = 641672820848. Its totient is φ = 641672820846.

The previous prime is 641672820821. The next prime is 641672820881. The reversal of 641672820847 is 748028276146.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 641672820847 - 2³⁵ = 607313082479 is a prime.

It is a super-3 number, since 3×641672820847³ (a number of 36 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641672821847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320836410423 + 320836410424.

It is an arithmetic number, because the mean of its divisors is an integer number (320836410424).

Almost surely, 2^641672820847 is an apocalyptic number.

641672820847 is a deficient number, since it is larger than the sum of its proper divisors (1).

641672820847 is an equidigital number, since it uses as much as digits as its factorization.

641672820847 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7225344, while the sum is 55.

The spelling of 641672820847 in words is "six hundred forty-one billion, six hundred seventy-two million, eight hundred twenty thousand, eight hundred forty-seven".