640242430 has 16 divisors (see below), whose sum is σ = 1213091280. Its totient is φ = 242618112.

The previous prime is 640242409. The next prime is 640242451. The reversal of 640242430 is 34242046.

It is an interprime number because it is at equal distance from previous prime (640242409) and next prime (640242451).

It is a junction number, because it is equal to n+sod(n) for n = 640242395 and 640242404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1684659 + ... + 1685038.

It is an arithmetic number, because the mean of its divisors is an integer number (75818205).

Almost surely, 2^640242430 is an apocalyptic number.

640242430 is a deficient number, since it is larger than the sum of its proper divisors (572848850).

640242430 is a wasteful number, since it uses less digits than its factorization.

640242430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3369723.

The product of its (nonzero) digits is 4608, while the sum is 25.

The square root of 640242430 is about 25303.0122712692. The cubic root of 640242430 is about 861.8826746934.

Adding to 640242430 its reverse (34242046), we get a palindrome (674484476).

The spelling of 640242430 in words is "six hundred forty million, two hundred forty-two thousand, four hundred thirty".