640331283 has 8 divisors (see below), whose sum is σ = 856690128. Its totient is φ = 425429984.

The previous prime is 640331239. The next prime is 640331297. The reversal of 640331283 is 382133046.

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 640331283 - 2¹³ = 640323091 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 640331283.

It is not an unprimeable number, because it can be changed into a prime (640331203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 363360 + ... + 365117.

It is an arithmetic number, because the mean of its divisors is an integer number (107086266).

Almost surely, 2^640331283 is an apocalyptic number.

640331283 is a deficient number, since it is larger than the sum of its proper divisors (216358845).

640331283 is a wasteful number, since it uses less digits than its factorization.

640331283 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728773.

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 640331283 is about 25304.7679894521. The cubic root of 640331283 is about 861.9225436115.

The spelling of 640331283 in words is "six hundred forty million, three hundred thirty-one thousand, two hundred eighty-three".