642861782 has 8 divisors (see below), whose sum is σ = 986718216. Its totient is φ = 313955712.

The previous prime is 642861781. The next prime is 642861797. The reversal of 642861782 is 287168246.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642861781) 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, 3737483 + ... + 3737654.

It is an arithmetic number, because the mean of its divisors is an integer number (123339777).

Almost surely, 2^642861782 is an apocalyptic number.

642861782 is a deficient number, since it is larger than the sum of its proper divisors (343856434).

642861782 is a wasteful number, since it uses less digits than its factorization.

642861782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7475182.

The product of its digits is 258048, while the sum is 44.

The square root of 642861782 is about 25354.7191268213. The cubic root of 642861782 is about 863.0564500535.

The spelling of 642861782 in words is "six hundred forty-two million, eight hundred sixty-one thousand, seven hundred eighty-two".