642019823 has 8 divisors (see below), whose sum is σ = 676556400. Its totient is φ = 607557888.

The previous prime is 642019789. The next prime is 642019849. The reversal of 642019823 is 328910246.

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

It is a cyclic number.

It is not a de Polignac number, because 642019823 - 2¹⁸ = 641757679 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642019853) 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, 536 + ... + 35837.

It is an arithmetic number, because the mean of its divisors is an integer number (84569550).

Almost surely, 2^642019823 is an apocalyptic number.

642019823 is a deficient number, since it is larger than the sum of its proper divisors (34536577).

642019823 is a wasteful number, since it uses less digits than its factorization.

642019823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37321.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 642019823 is about 25338.1100913229. The cubic root of 642019823 is about 862.6795024561.

The spelling of 642019823 in words is "six hundred forty-two million, nineteen thousand, eight hundred twenty-three".