640023230 has 64 divisors (see below), whose sum is σ = 1463505408. Its totient is φ = 195711360.

The previous prime is 640023229. The next prime is 640023239. The reversal of 640023230 is 32320046.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640023239) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32969 + ... + 48651.

It is an arithmetic number, because the mean of its divisors is an integer number (22867272).

Almost surely, 2^640023230 is an apocalyptic number.

640023230 is an abundant number, since it is smaller than the sum of its proper divisors (823482178).

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

640023230 is a wasteful number, since it uses less digits than its factorization.

640023230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15761.

The product of its (nonzero) digits is 864, while the sum is 20.

The square root of 640023230 is about 25298.6804003687. The cubic root of 640023230 is about 861.7843024528.

Adding to 640023230 its reverse (32320046), we get a palindrome (672343276).

The spelling of 640023230 in words is "six hundred forty million, twenty-three thousand, two hundred thirty".