642340784 has 80 divisors (see below), whose sum is σ = 1349913600. Its totient is φ = 295007232.

The previous prime is 642340781. The next prime is 642340789. The reversal of 642340784 is 487043246.

It is not an unprimeable number, because it can be changed into a prime (642340781) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3588407 + ... + 3588585.

It is an arithmetic number, because the mean of its divisors is an integer number (16873920).

Almost surely, 2^642340784 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642340784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (674956800).

642340784 is an abundant number, since it is smaller than the sum of its proper divisors (707572816).

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

642340784 is a wasteful number, since it uses less digits than its factorization.

642340784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450 (or 444 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 38.

The square root of 642340784 is about 25344.4428622923. The cubic root of 642340784 is about 862.8232365165.

The spelling of 642340784 in words is "six hundred forty-two million, three hundred forty thousand, seven hundred eighty-four".