1290385 has 24 divisors (see below), whose sum is σ = 1768320. Its totient is φ = 900864.

The previous prime is 1290379. The next prime is 1290427. The reversal of 1290385 is 5830921.

1290385 = T₉₂₆ + T₉₂₇ + T₉₂₈.

It is not a de Polignac number, because 1290385 - 2⁷ = 1290257 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27432 + ... + 27478.

It is an arithmetic number, because the mean of its divisors is an integer number (73680).

2^1290385 is an apocalyptic number.

1290385 is the 928-th centered triangular number.

It is an amenable number.

1290385 is a deficient number, since it is larger than the sum of its proper divisors (477935).

1290385 is a wasteful number, since it uses less digits than its factorization.

1290385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 1290385 is about 1135.9511433156. The cubic root of 1290385 is about 108.8695518827.

Subtracting from 1290385 its product of nonzero digits (2160), we obtain a square (1288225 = 1135²).

The spelling of 1290385 in words is "one million, two hundred ninety thousand, three hundred eighty-five".