1261500125 has 8 divisors (see below), whose sum is σ = 1574352312. Its totient is φ = 1009200000.

The previous prime is 1261500103. The next prime is 1261500133. The reversal of 1261500125 is 5210051621.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 107267449 + 1154232676 = 10357^2 + 33974^2 .

It is not a de Polignac number, because 1261500125 - 2⁶ = 1261500061 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1261500125.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5045876 + ... + 5046125.

It is an arithmetic number, because the mean of its divisors is an integer number (196794039).

Almost surely, 2^1261500125 is an apocalyptic number.

It is an amenable number.

1261500125 is a deficient number, since it is larger than the sum of its proper divisors (312852187).

1261500125 is an equidigital number, since it uses as much as digits as its factorization.

1261500125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10092016 (or 10092006 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 23.

The square root of 1261500125 is about 35517.6030300469. The cubic root of 1261500125 is about 1080.5107680620.

Adding to 1261500125 its reverse (5210051621), we get a palindrome (6471551746).

The spelling of 1261500125 in words is "one billion, two hundred sixty-one million, five hundred thousand, one hundred twenty-five".