816530625 has 75 divisors (see below), whose sum is σ = 1536302757. Its totient is φ = 432054000.

The previous prime is 816530599. The next prime is 816530629. The reversal of 816530625 is 526035618.

The square root of 816530625 is 28575.

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

It can be written as a sum of positive squares in 2 ways, for example, as 64016001 + 752514624 = 8001^2 + 27432^2 .

It is a tau number, because it is divible by the number of its divisors (75).

It is not a de Polignac number, because 816530625 - 2⁷ = 816530497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 816530625.

It is not an unprimeable number, because it can be changed into a prime (816530629) by changing a digit.

It is a polite number, since it can be written in 74 ways as a sum of consecutive naturals, for example, 6429312 + ... + 6429438.

Almost surely, 2^816530625 is an apocalyptic number.

816530625 is the 28575-th square number.

816530625 is the 14288-th centered octagonal number.

It is an amenable number.

816530625 is a deficient number, since it is larger than the sum of its proper divisors (719772132).

816530625 is an frugal number, since it uses more digits than its factorization.

816530625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286 (or 135 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The cubic root of 816530625 is about 934.6682552483.

Multiplying 816530625 by its sum of digits (36), we get a square (29395102500 = 171450²).

It can be divided in two parts, 816 and 530625, that added together give a 12-th power (531441 = 3¹²).

The spelling of 816530625 in words is "eight hundred sixteen million, five hundred thirty thousand, six hundred twenty-five".