640522505 has 8 divisors (see below), whose sum is σ = 878430912. Its totient is φ = 439215408.

The previous prime is 640522501. The next prime is 640522523. The reversal of 640522505 is 505225046.

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

It is a cyclic number.

It is not a de Polignac number, because 640522505 - 2² = 640522501 is a prime.

It is a super-2 number, since 2×640522505² = 820538158822950050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640522501) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 9150287 + ... + 9150356.

It is an arithmetic number, because the mean of its divisors is an integer number (109803864).

Almost surely, 2^640522505 is an apocalyptic number.

It is an amenable number.

640522505 is a deficient number, since it is larger than the sum of its proper divisors (237908407).

640522505 is a wasteful number, since it uses less digits than its factorization.

640522505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18300655.

The product of its (nonzero) digits is 12000, while the sum is 29.

The square root of 640522505 is about 25308.5460862532. The cubic root of 640522505 is about 862.0083336565.

The spelling of 640522505 in words is "six hundred forty million, five hundred twenty-two thousand, five hundred five".