721513423 has 2 divisors, whose sum is σ = 721513424. Its totient is φ = 721513422.

The previous prime is 721513361. The next prime is 721513447. The reversal of 721513423 is 324315127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721513423 - 2²⁵ = 687958991 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 721513391 and 721513400.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721513493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360756711 + 360756712.

It is an arithmetic number, because the mean of its divisors is an integer number (360756712).

Almost surely, 2^721513423 is an apocalyptic number.

721513423 is a deficient number, since it is larger than the sum of its proper divisors (1).

721513423 is an equidigital number, since it uses as much as digits as its factorization.

721513423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5040, while the sum is 28.

The square root of 721513423 is about 26861.0018986634. The cubic root of 721513423 is about 896.9084969509.

The spelling of 721513423 in words is "seven hundred twenty-one million, five hundred thirteen thousand, four hundred twenty-three".