16815625 has 12 divisors (see below), whose sum is σ = 21022092. Its totient is φ = 13450000.

The previous prime is 16815619. The next prime is 16815637. The reversal of 16815625 is 52651861.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 14930496 + 1885129 = 3864^2 + 1373^2 .

It is a de Polignac number, because none of the positive numbers 2^k-16815625 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 (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 435 + ... + 5815.

It is an arithmetic number, because the mean of its divisors is an integer number (1751841).

Almost surely, 2^16815625 is an apocalyptic number.

It is an amenable number.

16815625 is a deficient number, since it is larger than the sum of its proper divisors (4206467).

16815625 is an frugal number, since it uses more digits than its factorization.

16815625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5406 (or 5386 counting only the distinct ones).

The product of its digits is 14400, while the sum is 34.

The square root of 16815625 is about 4100.6859182337. The cubic root of 16815625 is about 256.1952093842.

It can be divided in two parts, 1681 and 5625, that multiplied together give a square (9455625 = 3075²).

The spelling of 16815625 in words is "sixteen million, eight hundred fifteen thousand, six hundred twenty-five".