651999726225 has 27 divisors (see below), whose sum is σ = 1167825648379. Its totient is φ = 347726727600.

The previous prime is 651999726211. The next prime is 651999726239. The reversal of 651999726225 is 522627999156.

The square root of 651999726225 is 807465.

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

651999726225 is a `hidden beast` number, since 6 + 519 + 9 + 97 + 2 + 6 + 2 + 25 = 666.

651999726225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (651999726211) and next prime (651999726239).

It can be written as a sum of positive squares in only one way, i.e., 234719901441 + 417279824784 = 484479^2 + 645972^2 .

It is not a de Polignac number, because 651999726225 - 2¹⁷ = 651999595153 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 12085060 + ... + 12138890.

Almost surely, 2^651999726225 is an apocalyptic number.

651999726225 is the 807465-th square number.

651999726225 is the 403733-rd centered octagonal number.

It is an amenable number.

651999726225 is a deficient number, since it is larger than the sum of its proper divisors (515825922154).

651999726225 is an frugal number, since it uses more digits than its factorization.

651999726225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107678 (or 53839 counting only the distinct ones).

The product of its digits is 36741600, while the sum is 63.

The spelling of 651999726225 in words is "six hundred fifty-one billion, nine hundred ninety-nine million, seven hundred twenty-six thousand, two hundred twenty-five".