640130242 has 8 divisors (see below), whose sum is σ = 962730000. Its totient is φ = 319220244.

The previous prime is 640130233. The next prime is 640130243. The reversal of 640130242 is 242031046.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (640130243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 421492 + ... + 423007.

It is an arithmetic number, because the mean of its divisors is an integer number (120341250).

Almost surely, 2^640130242 is an apocalyptic number.

640130242 is a deficient number, since it is larger than the sum of its proper divisors (322599758).

640130242 is a wasteful number, since it uses less digits than its factorization.

640130242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 844880.

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 640130242 is about 25300.7952839432. The cubic root of 640130242 is about 861.8323299400.

Adding to 640130242 its reverse (242031046), we get a palindrome (882161288).

The spelling of 640130242 in words is "six hundred forty million, one hundred thirty thousand, two hundred forty-two".