640852449 has 8 divisors (see below), whose sum is σ = 858046080. Its totient is φ = 425446896.

The previous prime is 640852423. The next prime is 640852453. The reversal of 640852449 is 944258046.

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

It is not a de Polignac number, because 640852449 - 2⁸ = 640852193 is a prime.

It is a super-2 number, since 2×640852449² = 821383722778595202, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 640852449.

It is not an unprimeable number, because it can be changed into a prime (640852409) 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, 446182 + ... + 447615.

It is an arithmetic number, because the mean of its divisors is an integer number (107255760).

Almost surely, 2^640852449 is an apocalyptic number.

It is an amenable number.

640852449 is a deficient number, since it is larger than the sum of its proper divisors (217193631).

640852449 is a wasteful number, since it uses less digits than its factorization.

640852449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 894039.

The product of its (nonzero) digits is 276480, while the sum is 42.

The square root of 640852449 is about 25315.0636775814. The cubic root of 640852449 is about 862.1563199509.

The spelling of 640852449 in words is "six hundred forty million, eight hundred fifty-two thousand, four hundred forty-nine".