641444197 has 2 divisors, whose sum is σ = 641444198. Its totient is φ = 641444196.

The previous prime is 641444179. The next prime is 641444249. The reversal of 641444197 is 791444146.

Together with previous prime (641444179) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 427290241 + 214153956 = 20671^2 + 14634^2 .

It is a cyclic number.

It is not a de Polignac number, because 641444197 - 2¹¹ = 641442149 is a prime.

It is a super-2 number, since 2×641444197² = 822901315729949618, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641444137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320722098 + 320722099.

It is an arithmetic number, because the mean of its divisors is an integer number (320722099).

Almost surely, 2^641444197 is an apocalyptic number.

It is an amenable number.

641444197 is a deficient number, since it is larger than the sum of its proper divisors (1).

641444197 is an equidigital number, since it uses as much as digits as its factorization.

641444197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 40.

The square root of 641444197 is about 25326.7486464410. The cubic root of 641444197 is about 862.4216032363.

The spelling of 641444197 in words is "six hundred forty-one million, four hundred forty-four thousand, one hundred ninety-seven".