642789523 has 4 divisors (see below), whose sum is σ = 642841128. Its totient is φ = 642737920.

The previous prime is 642789517. The next prime is 642789529. The reversal of 642789523 is 325987246.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (642789517) and next prime (642789529).

It is a cyclic number.

It is not a de Polignac number, because 642789523 - 2²⁵ = 609235091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642789529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5715 + ... + 36307.

It is an arithmetic number, because the mean of its divisors is an integer number (160710282).

Almost surely, 2^642789523 is an apocalyptic number.

642789523 is a deficient number, since it is larger than the sum of its proper divisors (51605).

642789523 is a wasteful number, since it uses less digits than its factorization.

642789523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51604.

The product of its digits is 725760, while the sum is 46.

The square root of 642789523 is about 25353.2941252217. The cubic root of 642789523 is about 863.0241123958.

The spelling of 642789523 in words is "six hundred forty-two million, seven hundred eighty-nine thousand, five hundred twenty-three".