641279533 has 2 divisors, whose sum is σ = 641279534. Its totient is φ = 641279532.

The previous prime is 641279503. The next prime is 641279543. The reversal of 641279533 is 335972146.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 477772164 + 163507369 = 21858^2 + 12787^2 .

It is a cyclic number.

It is not a de Polignac number, because 641279533 - 2²¹ = 639182381 is a prime.

It is a super-3 number, since 3×641279533³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641279503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320639766 + 320639767.

It is an arithmetic number, because the mean of its divisors is an integer number (320639767).

Almost surely, 2^641279533 is an apocalyptic number.

It is an amenable number.

641279533 is a deficient number, since it is larger than the sum of its proper divisors (1).

641279533 is an equidigital number, since it uses as much as digits as its factorization.

641279533 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 40.

The square root of 641279533 is about 25323.4976454675. The cubic root of 641279533 is about 862.3478000149.

The spelling of 641279533 in words is "six hundred forty-one million, two hundred seventy-nine thousand, five hundred thirty-three".