640243452 has 24 divisors (see below), whose sum is σ = 1504652800. Its totient is φ = 211878576.

The previous prime is 640243451. The next prime is 640243453. The reversal of 640243452 is 254342046.

It is an interprime number because it is at equal distance from previous prime (640243451) and next prime (640243453).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640243451) 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, 190252 + ... + 193587.

Almost surely, 2^640243452 is an apocalyptic number.

It is an amenable number.

640243452 is an abundant number, since it is smaller than the sum of its proper divisors (864409348).

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

640243452 is a wasteful number, since it uses less digits than its factorization.

640243452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383985 (or 383983 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 30.

The square root of 640243452 is about 25303.0324664851. The cubic root of 640243452 is about 861.8831332924.

Adding to 640243452 its reverse (254342046), we get a palindrome (894585498).

It can be divided in two parts, 64024 and 3452, that added together give a palindrome (67476).

The spelling of 640243452 in words is "six hundred forty million, two hundred forty-three thousand, four hundred fifty-two".