651221255464 has 32 divisors (see below), whose sum is σ = 1350505626120. Its totient is φ = 292440312576.

The previous prime is 651221255453. The next prime is 651221255519. The reversal of 651221255464 is 464552122156.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 634491902500 + 16729352964 = 796550^2 + 129342^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 651221255464.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84614299 + ... + 84621994.

Almost surely, 2^651221255464 is an apocalyptic number.

It is an amenable number.

651221255464 is an abundant number, since it is smaller than the sum of its proper divisors (699284370656).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

651221255464 is a wasteful number, since it uses less digits than its factorization.

651221255464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169236349 (or 169236345 counting only the distinct ones).

The product of its digits is 576000, while the sum is 43.

The spelling of 651221255464 in words is "six hundred fifty-one billion, two hundred twenty-one million, two hundred fifty-five thousand, four hundred sixty-four".