533991721 has 2 divisors, whose sum is σ = 533991722. Its totient is φ = 533991720.

The previous prime is 533991691. The next prime is 533991727. The reversal of 533991721 is 127199335.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 370023696 + 163968025 = 19236^2 + 12805^2 .

It is a cyclic number.

It is not a de Polignac number, because 533991721 - 2⁷ = 533991593 is a prime.

It is not a weakly prime, because it can be changed into another prime (533991727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 266995860 + 266995861.

It is an arithmetic number, because the mean of its divisors is an integer number (266995861).

Almost surely, 2^533991721 is an apocalyptic number.

It is an amenable number.

533991721 is a deficient number, since it is larger than the sum of its proper divisors (1).

533991721 is an equidigital number, since it uses as much as digits as its factorization.

533991721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51030, while the sum is 40.

The square root of 533991721 is about 23108.2608822040. The cubic root of 533991721 is about 811.2938327523.

The spelling of 533991721 in words is "five hundred thirty-three million, nine hundred ninety-one thousand, seven hundred twenty-one".