1640985 has 16 divisors (see below), whose sum is σ = 2711040. Its totient is φ = 846720.

The previous prime is 1640971. The next prime is 1641007. The reversal of 1640985 is 5890461.

It is not a de Polignac number, because 1640985 - 2⁵ = 1640953 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1300 + ... + 2229.

It is an arithmetic number, because the mean of its divisors is an integer number (169440).

2^1640985 is an apocalyptic number.

1640985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1640985 is a deficient number, since it is larger than the sum of its proper divisors (1070055).

1640985 is a wasteful number, since it uses less digits than its factorization.

1640985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3568.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 1640985 is about 1281.0093676472. The cubic root of 1640985 is about 117.9509755174.

The spelling of 1640985 in words is "one million, six hundred forty thousand, nine hundred eighty-five".