640285242 has 16 divisors (see below), whose sum is σ = 1298607552. Its totient is φ = 210422240.

The previous prime is 640285241. The next prime is 640285249. The reversal of 640285242 is 242582046.

It is a super-2 number, since 2×640285242² = 819930382245997128, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (640285241) 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, 751083 + ... + 751934.

It is an arithmetic number, because the mean of its divisors is an integer number (81162972).

Almost surely, 2^640285242 is an apocalyptic number.

640285242 is an abundant number, since it is smaller than the sum of its proper divisors (658322310).

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

640285242 is a wasteful number, since it uses less digits than its factorization.

640285242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1503093.

The product of its (nonzero) digits is 30720, while the sum is 33.

The square root of 640285242 is about 25303.8582433589. The cubic root of 640285242 is about 861.9018851763.

The spelling of 640285242 in words is "six hundred forty million, two hundred eighty-five thousand, two hundred forty-two".