721428451 has 2 divisors, whose sum is σ = 721428452. Its totient is φ = 721428450.

The previous prime is 721428443. The next prime is 721428493. The reversal of 721428451 is 154824127.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 721428451 - 2³ = 721428443 is a prime.

It is not a weakly prime, because it can be changed into another prime (721420451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360714225 + 360714226.

It is an arithmetic number, because the mean of its divisors is an integer number (360714226).

Almost surely, 2^721428451 is an apocalyptic number.

721428451 is a deficient number, since it is larger than the sum of its proper divisors (1).

721428451 is an equidigital number, since it uses as much as digits as its factorization.

721428451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17920, while the sum is 34.

The square root of 721428451 is about 26859.4201538306. The cubic root of 721428451 is about 896.8732861942.

The spelling of 721428451 in words is "seven hundred twenty-one million, four hundred twenty-eight thousand, four hundred fifty-one".