1281787625 has 16 divisors (see below), whose sum is σ = 1609276032. Its totient is φ = 1019273200.

The previous prime is 1281787609. The next prime is 1281787679. The reversal of 1281787625 is 5267871821.

It is not a de Polignac number, because 1281787625 - 2⁴ = 1281787609 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 1281787625.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9827 + ... + 51576.

It is an arithmetic number, because the mean of its divisors is an integer number (100579752).

Almost surely, 2^1281787625 is an apocalyptic number.

It is an amenable number.

1281787625 is a deficient number, since it is larger than the sum of its proper divisors (327488407).

1281787625 is an equidigital number, since it uses as much as digits as its factorization.

1281787625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61585 (or 61575 counting only the distinct ones).

The product of its digits is 376320, while the sum is 47.

The square root of 1281787625 is about 35802.0617423075. The cubic root of 1281787625 is about 1086.2722657667.

The spelling of 1281787625 in words is "one billion, two hundred eighty-one million, seven hundred eighty-seven thousand, six hundred twenty-five".