640901219 has 8 divisors (see below), whose sum is σ = 732697440. Its totient is φ = 549164736.

The previous prime is 640901171. The next prime is 640901221. The reversal of 640901219 is 912109046.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640901219 is a prime.

It is a super-2 number, since 2×640901219² = 821508745031371922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640901119) 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, 11087 + ... + 37479.

It is an arithmetic number, because the mean of its divisors is an integer number (91587180).

Almost surely, 2^640901219 is an apocalyptic number.

640901219 is a deficient number, since it is larger than the sum of its proper divisors (91796221).

640901219 is a wasteful number, since it uses less digits than its factorization.

640901219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29869.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 640901219 is about 25316.0269197202. The cubic root of 640901219 is about 862.1781899343.

The spelling of 640901219 in words is "six hundred forty million, nine hundred one thousand, two hundred nineteen".