640621623322 has 32 divisors (see below), whose sum is σ = 999372273984. Its totient is φ = 307738569600.

The previous prime is 640621623319. The next prime is 640621623329. The reversal of 640621623322 is 223326126046.

It is not an unprimeable number, because it can be changed into a prime (640621623329) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19602748 + ... + 19635400.

It is an arithmetic number, because the mean of its divisors is an integer number (31230383562).

Almost surely, 2^640621623322 is an apocalyptic number.

640621623322 is a deficient number, since it is larger than the sum of its proper divisors (358750650662).

640621623322 is a wasteful number, since it uses less digits than its factorization.

640621623322 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36334.

The product of its (nonzero) digits is 124416, while the sum is 37.

Adding to 640621623322 its reverse (223326126046), we get a palindrome (863947749368).

The spelling of 640621623322 in words is "six hundred forty billion, six hundred twenty-one million, six hundred twenty-three thousand, three hundred twenty-two".