721533523 has 2 divisors, whose sum is σ = 721533524. Its totient is φ = 721533522.

The previous prime is 721533521. The next prime is 721533563. The reversal of 721533523 is 325335127.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 721533523 - 2¹ = 721533521 is a prime.

It is a super-2 number, since 2×721533523² = 1041221249625583058, which contains 22 as substring.

Together with 721533521, it forms a pair of twin primes.

It is equal to p_37309333 and since 721533523 and 37309333 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (721533521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360766761 + 360766762.

It is an arithmetic number, because the mean of its divisors is an integer number (360766762).

Almost surely, 2^721533523 is an apocalyptic number.

721533523 is a deficient number, since it is larger than the sum of its proper divisors (1).

721533523 is an equidigital number, since it uses as much as digits as its factorization.

721533523 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18900, while the sum is 31.

The square root of 721533523 is about 26861.3760444248. The cubic root of 721533523 is about 896.9168255986.

The spelling of 721533523 in words is "seven hundred twenty-one million, five hundred thirty-three thousand, five hundred twenty-three".