640499073806 has 8 divisors (see below), whose sum is σ = 961075515960. Its totient is φ = 320140568488.

The previous prime is 640499073803. The next prime is 640499073829. The reversal of 640499073806 is 608370994046.

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 (640499073803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54476861 + ... + 54488616.

It is an arithmetic number, because the mean of its divisors is an integer number (120134439495).

Almost surely, 2^640499073806 is an apocalyptic number.

640499073806 is a deficient number, since it is larger than the sum of its proper divisors (320576442154).

640499073806 is a wasteful number, since it uses less digits than its factorization.

640499073806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108968418.

The product of its (nonzero) digits is 7838208, while the sum is 56.

The spelling of 640499073806 in words is "six hundred forty billion, four hundred ninety-nine million, seventy-three thousand, eight hundred six".