641143957 has 2 divisors, whose sum is σ = 641143958. Its totient is φ = 641143956.

The previous prime is 641143927. The next prime is 641143981. The reversal of 641143957 is 759341146.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 575712036 + 65431921 = 23994^2 + 8089^2 .

It is a cyclic number.

It is not a de Polignac number, because 641143957 - 2¹⁵ = 641111189 is a prime.

It is a super-2 number, since 2×641143957² = 822131147195235698, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641143927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320571978 + 320571979.

It is an arithmetic number, because the mean of its divisors is an integer number (320571979).

Almost surely, 2^641143957 is an apocalyptic number.

It is an amenable number.

641143957 is a deficient number, since it is larger than the sum of its proper divisors (1).

641143957 is an equidigital number, since it uses as much as digits as its factorization.

641143957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 40.

The square root of 641143957 is about 25320.8206225628. The cubic root of 641143957 is about 862.2870246955.

The spelling of 641143957 in words is "six hundred forty-one million, one hundred forty-three thousand, nine hundred fifty-seven".