640003394 has 8 divisors (see below), whose sum is σ = 960329100. Its totient is φ = 319893696.

The previous prime is 640003327. The next prime is 640003409. The reversal of 640003394 is 493300046.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 552861169 + 87142225 = 23513^2 + 9335^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46379 + ... + 58574.

Almost surely, 2^640003394 is an apocalyptic number.

640003394 is a deficient number, since it is larger than the sum of its proper divisors (320325706).

640003394 is a wasteful number, since it uses less digits than its factorization.

640003394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108004.

The product of its (nonzero) digits is 7776, while the sum is 29.

The square root of 640003394 is about 25298.2883610730. The cubic root of 640003394 is about 861.7753993749.

The spelling of 640003394 in words is "six hundred forty million, three thousand, three hundred ninety-four".