721045225 has 12 divisors (see below), whose sum is σ = 946690524. Its totient is φ = 542904320.

The previous prime is 721045211. The next prime is 721045243. The reversal of 721045225 is 522540127.

It can be written as a sum of positive squares in 6 ways, for example, as 47279376 + 673765849 = 6876^2 + 25957^2 .

It is not a de Polignac number, because 721045225 - 2⁷ = 721045097 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 721045193 and 721045202.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 847864 + ... + 848713.

It is an arithmetic number, because the mean of its divisors is an integer number (78890877).

Almost surely, 2^721045225 is an apocalyptic number.

It is an amenable number.

721045225 is a deficient number, since it is larger than the sum of its proper divisors (225645299).

721045225 is a wasteful number, since it uses less digits than its factorization.

721045225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1696604 (or 1696599 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 28.

The square root of 721045225 is about 26852.2852844967. The cubic root of 721045225 is about 896.7144503740.

The spelling of 721045225 in words is "seven hundred twenty-one million, forty-five thousand, two hundred twenty-five".