521274991 has 2 divisors, whose sum is σ = 521274992. Its totient is φ = 521274990.

The previous prime is 521274983. The next prime is 521275021. The reversal of 521274991 is 199472125.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 521274991 - 2³ = 521274983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521274911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260637495 + 260637496.

It is an arithmetic number, because the mean of its divisors is an integer number (260637496).

Almost surely, 2^521274991 is an apocalyptic number.

521274991 is a deficient number, since it is larger than the sum of its proper divisors (1).

521274991 is an equidigital number, since it uses as much as digits as its factorization.

521274991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 40.

The square root of 521274991 is about 22831.4474136004. The cubic root of 521274991 is about 804.8018446724.

The spelling of 521274991 in words is "five hundred twenty-one million, two hundred seventy-four thousand, nine hundred ninety-one".