1640490 has 32 divisors (see below), whose sum is σ = 3974400. Its totient is φ = 433344.

The previous prime is 1640467. The next prime is 1640497. The reversal of 1640490 is 940461.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1640490.

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

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4287 + ... + 4653.

It is an arithmetic number, because the mean of its divisors is an integer number (124200).

2^1640490 is an apocalyptic number.

1640490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1640490 is an abundant number, since it is smaller than the sum of its proper divisors (2333910).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640490 is a wasteful number, since it uses less digits than its factorization.

1640490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 1640490 is about 1280.8161460569. The cubic root of 1640490 is about 117.9391144290.

The spelling of 1640490 in words is "one million, six hundred forty thousand, four hundred ninety".