1231912225 has 24 divisors (see below), whose sum is σ = 1661163768. Its totient is φ = 902476800.

The previous prime is 1231912217. The next prime is 1231912237. The reversal of 1231912225 is 5222191321.

It can be written as a sum of positive squares in 12 ways, for example, as 463761 + 1231448464 = 681^2 + 35092^2 .

It is not a de Polignac number, because 1231912225 - 2³ = 1231912217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1231912193 and 1231912202.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23446 + ... + 54895.

It is an arithmetic number, because the mean of its divisors is an integer number (69215157).

Almost surely, 2^1231912225 is an apocalyptic number.

It is an amenable number.

1231912225 is a deficient number, since it is larger than the sum of its proper divisors (429251543).

1231912225 is a wasteful number, since it uses less digits than its factorization.

1231912225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78405 (or 78400 counting only the distinct ones).

The product of its digits is 2160, while the sum is 28.

The square root of 1231912225 is about 35098.6071660971. The cubic root of 1231912225 is about 1071.9962225237.

The spelling of 1231912225 in words is "one billion, two hundred thirty-one million, nine hundred twelve thousand, two hundred twenty-five".