648262521 has 63 divisors (see below), whose sum is σ = 1041431167. Its totient is φ = 403302240.

The previous prime is 648262519. The next prime is 648262529. The reversal of 648262521 is 125262846.

It is a happy number.

The square root of 648262521 is 25461.

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

648262521 is a `hidden beast` number, since 6 + 4 + 8 + 2 + 625 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 31236921 + 617025600 = 5589^2 + 24840^2 .

It is not a de Polignac number, because 648262521 - 2¹ = 648262519 is a prime.

It is a super-2 number, since 2×648262521² = 840488592266550882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648262529) by changing a digit.

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 62 ways as a sum of consecutive naturals, for example, 15811261 + ... + 15811301.

Almost surely, 2^648262521 is an apocalyptic number.

648262521 is the 25461-st square number.

648262521 is the 12731-st centered octagonal number.

It is an amenable number.

648262521 is a deficient number, since it is larger than the sum of its proper divisors (393168646).

648262521 is an frugal number, since it uses more digits than its factorization.

648262521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146 (or 67 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The cubic root of 648262521 is about 865.4665846787.

Multiplying 648262521 by its sum of digits (36), we get a square (23337450756 = 152766²).

It can be divided in two parts, 648 and 262521, that added together give a square (263169 = 513²).

The spelling of 648262521 in words is "six hundred forty-eight million, two hundred sixty-two thousand, five hundred twenty-one".