640219530 has 16 divisors (see below), whose sum is σ = 1536526944. Its totient is φ = 170725200.

The previous prime is 640219523. The next prime is 640219537. The reversal of 640219530 is 35912046.

It is an interprime number because it is at equal distance from previous prime (640219523) and next prime (640219537).

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 21340651 = 640219530 / (6 + 4 + 0 + 2 + 1 + 9 + 5 + 3 + 0).

It is not an unprimeable number, because it can be changed into a prime (640219537) 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, 10670296 + ... + 10670355.

It is an arithmetic number, because the mean of its divisors is an integer number (96032934).

Almost surely, 2^640219530 is an apocalyptic number.

640219530 is an abundant number, since it is smaller than the sum of its proper divisors (896307414).

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

640219530 is a wasteful number, since it uses less digits than its factorization.

640219530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21340661.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 640219530 is about 25302.5597519302. The cubic root of 640219530 is about 861.8723987169.

The spelling of 640219530 in words is "six hundred forty million, two hundred nineteen thousand, five hundred thirty".