642748736 has 28 divisors (see below), whose sum is σ = 1457663328. Its totient is φ = 275463552.

The previous prime is 642748627. The next prime is 642748741. The reversal of 642748736 is 637847246.

It is a tau number, because it is divible by the number of its divisors (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 716906 + ... + 717801.

Almost surely, 2^642748736 is an apocalyptic number.

It is an amenable number.

642748736 is an abundant number, since it is smaller than the sum of its proper divisors (814914592).

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

642748736 is a wasteful number, since it uses less digits than its factorization.

642748736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1434726 (or 1434716 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 47.

The square root of 642748736 is about 25352.4897396686. The cubic root of 642748736 is about 863.0058581525.

The spelling of 642748736 in words is "six hundred forty-two million, seven hundred forty-eight thousand, seven hundred thirty-six".