1291825 has 6 divisors (see below), whose sum is σ = 1601894. Its totient is φ = 1033440.

The previous prime is 1291819. The next prime is 1291831. The reversal of 1291825 is 5281921.

It is an interprime number because it is at equal distance from previous prime (1291819) and next prime (1291831).

It can be written as a sum of positive squares in 3 ways, for example, as 400689 + 891136 = 633^2 + 944^2 .

It is not a de Polignac number, because 1291825 - 2³ = 1291817 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1291793 and 1291802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 25812 + ... + 25861.

2^1291825 is an apocalyptic number.

It is an amenable number.

1291825 is a deficient number, since it is larger than the sum of its proper divisors (310069).

1291825 is an equidigital number, since it uses as much as digits as its factorization.

1291825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51683 (or 51678 counting only the distinct ones).

The product of its digits is 1440, while the sum is 28.

The square root of 1291825 is about 1136.5847966606. The cubic root of 1291825 is about 108.9100343419.

It can be divided in two parts, 1291 and 825, that added together give a square (2116 = 46²).

The spelling of 1291825 in words is "one million, two hundred ninety-one thousand, eight hundred twenty-five".