612721045225 has 27 divisors (see below), whose sum is σ = 807183317647. Its totient is φ = 461292807680.

The previous prime is 612721045207. The next prime is 612721045249. The reversal of 612721045225 is 522540127216.

The square root of 612721045225 is 782765.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 443072615769 + 169648429456 = 665637^2 + 411884^2 .

It is a de Polignac number, because none of the positive numbers 2^k-612721045225 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 66530421 + ... + 66539629.

Almost surely, 2^612721045225 is an apocalyptic number.

612721045225 is the 782765-th square number.

612721045225 is the 391383-rd centered octagonal number.

It is an amenable number.

612721045225 is a deficient number, since it is larger than the sum of its proper divisors (194462272422).

612721045225 is an frugal number, since it uses more digits than its factorization.

612721045225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18462 (or 9231 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 37.

The spelling of 612721045225 in words is "six hundred twelve billion, seven hundred twenty-one million, forty-five thousand, two hundred twenty-five".