1281957725 has 24 divisors (see below), whose sum is σ = 1650251520. Its totient is φ = 986832000.

The previous prime is 1281957713. The next prime is 1281957737. The reversal of 1281957725 is 5277591821.

It is an interprime number because it is at equal distance from previous prime (1281957713) and next prime (1281957737).

It is not a de Polignac number, because 1281957725 - 2⁶ = 1281957661 is a prime.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1281957725.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 134105 + ... + 143345.

It is an arithmetic number, because the mean of its divisors is an integer number (68760480).

Almost surely, 2^1281957725 is an apocalyptic number.

It is an amenable number.

1281957725 is a deficient number, since it is larger than the sum of its proper divisors (368293795).

1281957725 is a wasteful number, since it uses less digits than its factorization.

1281957725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9461 (or 9456 counting only the distinct ones).

The product of its digits is 352800, while the sum is 47.

The square root of 1281957725 is about 35804.4372250144. The cubic root of 1281957725 is about 1086.3203150004.

The spelling of 1281957725 in words is "one billion, two hundred eighty-one million, nine hundred fifty-seven thousand, seven hundred twenty-five".