816563825 has 48 divisors (see below), whose sum is σ = 1317344256. Its totient is φ = 486868800.

The previous prime is 816563807. The next prime is 816563837. The reversal of 816563825 is 528365618.

816563825 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 816563825 - 2⁸ = 816563569 is a prime.

It is a super-3 number, since 3×816563825³ (a number of 28 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 35054 + ... + 53496.

It is an arithmetic number, because the mean of its divisors is an integer number (27444672).

Almost surely, 2^816563825 is an apocalyptic number.

It is an amenable number.

816563825 is a deficient number, since it is larger than the sum of its proper divisors (500780431).

816563825 is a wasteful number, since it uses less digits than its factorization.

816563825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18494 (or 18489 counting only the distinct ones).

The product of its digits is 345600, while the sum is 44.

The square root of 816563825 is about 28575.5809214791. The cubic root of 816563825 is about 934.6809228955.

It can be divided in two parts, 8165 and 63825, that multiplied together give a palindrome (521131125).

The spelling of 816563825 in words is "eight hundred sixteen million, five hundred sixty-three thousand, eight hundred twenty-five".