1640493 has 24 divisors (see below), whose sum is σ = 2530528. Its totient is φ = 1061424.

The previous prime is 1640467. The next prime is 1640497. The reversal of 1640493 is 3940461.

It is not a de Polignac number, because 1640493 - 2⁵ = 1640461 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640497) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10371 + ... + 10527.

2^1640493 is an apocalyptic number.

It is an amenable number.

1640493 is a deficient number, since it is larger than the sum of its proper divisors (890035).

1640493 is an equidigital number, since it uses as much as digits as its factorization.

1640493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 1640493 is about 1280.8173171846. The cubic root of 1640493 is about 117.9391863216.

Subtracting 1640493 from its reverse (3940461), we obtain a cube (2299968 = 132³).

The spelling of 1640493 in words is "one million, six hundred forty thousand, four hundred ninety-three".