721425 has 12 divisors (see below), whose sum is σ = 1192880. Its totient is φ = 384720.

The previous prime is 721397. The next prime is 721439. The reversal of 721425 is 524127.

It is not a de Polignac number, because 721425 - 2⁸ = 721169 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 721425.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4735 + ... + 4884.

2⁷²¹⁴²⁵ is an apocalyptic number.

721425 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

721425 is a deficient number, since it is larger than the sum of its proper divisors (471455).

721425 is a wasteful number, since it uses less digits than its factorization.

721425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9632 (or 9627 counting only the distinct ones).

The product of its digits is 560, while the sum is 21.

The square root of 721425 is about 849.3674116659. The cubic root of 721425 is about 89.6871856108.

The spelling of 721425 in words is "seven hundred twenty-one thousand, four hundred twenty-five".