640471856322 has 32 divisors (see below), whose sum is σ = 1322608250880. Its totient is φ = 206550110160.

The previous prime is 640471856243. The next prime is 640471856351. The reversal of 640471856322 is 223658174046.

It is a super-2 number, since 2×640471856322² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 272829 + ... + 1164207.

It is an arithmetic number, because the mean of its divisors is an integer number (41331507840).

Almost surely, 2^640471856322 is an apocalyptic number.

640471856322 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

640471856322 is an abundant number, since it is smaller than the sum of its proper divisors (682136394558).

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

640471856322 is a wasteful number, since it uses less digits than its factorization.

640471856322 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 895278.

The product of its (nonzero) digits is 1935360, while the sum is 48.

The spelling of 640471856322 in words is "six hundred forty billion, four hundred seventy-one million, eight hundred fifty-six thousand, three hundred twenty-two".