1390881 has 4 divisors (see below), whose sum is σ = 1854512. Its totient is φ = 927252.

The previous prime is 1390859. The next prime is 1390891. The reversal of 1390881 is 1880931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1390881 - 2⁹ = 1390369 is a prime.

It is a super-2 number, since 2×1390881² = 3869099912322, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1390801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 231811 + ... + 231816.

It is an arithmetic number, because the mean of its divisors is an integer number (463628).

2^1390881 is an apocalyptic number.

It is an amenable number.

1390881 is a deficient number, since it is larger than the sum of its proper divisors (463631).

1390881 is an equidigital number, since it uses as much as digits as its factorization.

1390881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 463630.

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 1390881 is about 1179.3561802950. The cubic root of 1390881 is about 111.6254762562.

The spelling of 1390881 in words is "one million, three hundred ninety thousand, eight hundred eighty-one".