1281825 has 36 divisors (see below), whose sum is σ = 2392208. Its totient is φ = 680400.

The previous prime is 1281823. The next prime is 1281827. The reversal of 1281825 is 5281821.

It is an interprime number because it is at equal distance from previous prime (1281823) and next prime (1281827).

It is not a de Polignac number, because 1281825 - 2¹ = 1281823 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1281821) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 5970 + ... + 6180.

2^1281825 is an apocalyptic number.

1281825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1281825 is a deficient number, since it is larger than the sum of its proper divisors (1110383).

1281825 is an equidigital number, since it uses as much as digits as its factorization.

1281825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236 (or 219 counting only the distinct ones).

The product of its digits is 1280, while the sum is 27.

The square root of 1281825 is about 1132.1771062868. The cubic root of 1281825 is about 108.6282823686.

It can be divided in two parts, 128 and 1825, that added together give a triangular number (1953 = T₆₂).

The spelling of 1281825 in words is "one million, two hundred eighty-one thousand, eight hundred twenty-five".