7811908225 has 27 divisors (see below), whose sum is σ = 10654067011. Its totient is φ = 5677852400.

The previous prime is 7811908201. The next prime is 7811908229. The reversal of 7811908225 is 5228091187.

It is a happy number.

The square root of 7811908225 is 88385.

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

It can be written as a sum of positive squares in only one way, i.e., 2812286961 + 4999621264 = 53031^2 + 70708^2 .

It is not a de Polignac number, because 7811908225 - 2²¹ = 7809811073 is a prime.

It is a super-2 number, since 2×7811908225² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7811908229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4860372 + ... + 4861978.

Almost surely, 2^7811908225 is an apocalyptic number.

7811908225 is the 88385-th square number.

7811908225 is the 44193-rd centered octagonal number.

It is an amenable number.

7811908225 is a deficient number, since it is larger than the sum of its proper divisors (2842158786).

7811908225 is an equidigital number, since it uses as much as digits as its factorization.

7811908225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3246 (or 1623 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 43.

The cubic root of 7811908225 is about 1984.2012132015.

The spelling of 7811908225 in words is "seven billion, eight hundred eleven million, nine hundred eight thousand, two hundred twenty-five".