521404447 has 2 divisors, whose sum is σ = 521404448. Its totient is φ = 521404446.

The previous prime is 521404397. The next prime is 521404459. The reversal of 521404447 is 744404125.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 521404447 - 2¹⁵ = 521371679 is a prime.

It is a super-3 number, since 3×521404447³ (a number of 27 digits) contains 333 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 (521404547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260702223 + 260702224.

It is an arithmetic number, because the mean of its divisors is an integer number (260702224).

Almost surely, 2^521404447 is an apocalyptic number.

521404447 is a deficient number, since it is larger than the sum of its proper divisors (1).

521404447 is an equidigital number, since it uses as much as digits as its factorization.

521404447 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17920, while the sum is 31.

The square root of 521404447 is about 22834.2822746851. The cubic root of 521404447 is about 804.8684619767.

The spelling of 521404447 in words is "five hundred twenty-one million, four hundred four thousand, four hundred forty-seven".