1690491 has 12 divisors (see below), whose sum is σ = 2478056. Its totient is φ = 1024320.

The previous prime is 1690483. The next prime is 1690519. The reversal of 1690491 is 1940961.

It is not a de Polignac number, because 1690491 - 2³ = 1690483 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (1690421) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1966 + ... + 2691.

2^1690491 is an apocalyptic number.

1690491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1690491 is a deficient number, since it is larger than the sum of its proper divisors (787565).

1690491 is a wasteful number, since it uses less digits than its factorization.

1690491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4682 (or 4671 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 1690491 is about 1300.1888324393. The cubic root of 1690491 is about 119.1253768853.

The spelling of 1690491 in words is "one million, six hundred ninety thousand, four hundred ninety-one".