721721454 has 16 divisors (see below), whose sum is σ = 1464987648. Its totient is φ = 236983032.

The previous prime is 721721449. The next prime is 721721467. The reversal of 721721454 is 454127127.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 897262 + ... + 898065.

It is an arithmetic number, because the mean of its divisors is an integer number (91561728).

Almost surely, 2^721721454 is an apocalyptic number.

721721454 is an abundant number, since it is smaller than the sum of its proper divisors (743266194).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721721454 is a wasteful number, since it uses less digits than its factorization.

721721454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1795399.

The product of its digits is 15680, while the sum is 33.

The square root of 721721454 is about 26864.8739807206. The cubic root of 721721454 is about 896.9946893146.

The spelling of 721721454 in words is "seven hundred twenty-one million, seven hundred twenty-one thousand, four hundred fifty-four".