521959943 has 2 divisors, whose sum is σ = 521959944. Its totient is φ = 521959942.

The previous prime is 521959913. The next prime is 521960069. The reversal of 521959943 is 349959125.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 521959943 - 2²⁰ = 520911367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521959913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260979971 + 260979972.

It is an arithmetic number, because the mean of its divisors is an integer number (260979972).

Almost surely, 2^521959943 is an apocalyptic number.

521959943 is a deficient number, since it is larger than the sum of its proper divisors (1).

521959943 is an equidigital number, since it uses as much as digits as its factorization.

521959943 is an evil number, because the sum of its binary digits is even.

The product of its digits is 437400, while the sum is 47.

The square root of 521959943 is about 22846.4426771434. The cubic root of 521959943 is about 805.1541918801.

The spelling of 521959943 in words is "five hundred twenty-one million, nine hundred fifty-nine thousand, nine hundred forty-three".