1640398 has 8 divisors (see below), whose sum is σ = 2605392. Its totient is φ = 771936.

The previous prime is 1640393. The next prime is 1640399. The reversal of 1640398 is 8930461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24090 + ... + 24157.

It is an arithmetic number, because the mean of its divisors is an integer number (325674).

2^1640398 is an apocalyptic number.

1640398 is a deficient number, since it is larger than the sum of its proper divisors (964994).

1640398 is a wasteful number, since it uses less digits than its factorization.

1640398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48266.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 1640398 is about 1280.7802309530. The cubic root of 1640398 is about 117.9369096810.

The spelling of 1640398 in words is "one million, six hundred forty thousand, three hundred ninety-eight".