721427 has 6 divisors (see below), whose sum is σ = 839268. Its totient is φ = 618324.

The previous prime is 721397. The next prime is 721439. The reversal of 721427 is 724127.

It is not a de Polignac number, because 721427 - 2⁶ = 721363 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (727427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7313 + ... + 7410.

It is an arithmetic number, because the mean of its divisors is an integer number (139878).

2⁷²¹⁴²⁷ is an apocalyptic number.

721427 is a deficient number, since it is larger than the sum of its proper divisors (117841).

721427 is a wasteful number, since it uses less digits than its factorization.

721427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14737 (or 14730 counting only the distinct ones).

The product of its digits is 784, while the sum is 23.

The square root of 721427 is about 849.3685890119. The cubic root of 721427 is about 89.6872684904.

The spelling of 721427 in words is "seven hundred twenty-one thousand, four hundred twenty-seven", and thus it is an iban number.