15881225 has 6 divisors (see below), whose sum is σ = 19692750. Its totient is φ = 12704960.

The previous prime is 15881197. The next prime is 15881231. The reversal of 15881225 is 52218851.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 4239481 + 11641744 = 2059^2 + 3412^2 .

It is not a de Polignac number, because 15881225 - 2⁶ = 15881161 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 15881191 and 15881200.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 317600 + ... + 317649.

It is an arithmetic number, because the mean of its divisors is an integer number (3282125).

Almost surely, 2^15881225 is an apocalyptic number.

It is an amenable number.

15881225 is a deficient number, since it is larger than the sum of its proper divisors (3811525).

15881225 is an equidigital number, since it uses as much as digits as its factorization.

15881225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 635259 (or 635254 counting only the distinct ones).

The product of its digits is 6400, while the sum is 32.

The square root of 15881225 is about 3985.1254685392. The cubic root of 15881225 is about 251.3591309950.

The spelling of 15881225 in words is "fifteen million, eight hundred eighty-one thousand, two hundred twenty-five".