641166437 has 2 divisors, whose sum is σ = 641166438. Its totient is φ = 641166436.

The previous prime is 641166391. The next prime is 641166467. The reversal of 641166437 is 734661146.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 475632481 + 165533956 = 21809^2 + 12866^2 .

It is a cyclic number.

It is not a de Polignac number, because 641166437 - 2²⁶ = 574057573 is a prime.

It is a super-2 number, since 2×641166437² = 822188799870549938, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 641166437.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641166467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320583218 + 320583219.

It is an arithmetic number, because the mean of its divisors is an integer number (320583219).

Almost surely, 2^641166437 is an apocalyptic number.

It is an amenable number.

641166437 is a deficient number, since it is larger than the sum of its proper divisors (1).

641166437 is an equidigital number, since it uses as much as digits as its factorization.

641166437 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 38.

The square root of 641166437 is about 25321.2645221363. The cubic root of 641166437 is about 862.2971025080.

The spelling of 641166437 in words is "six hundred forty-one million, one hundred sixty-six thousand, four hundred thirty-seven".