642157011323 has 4 divisors (see below), whose sum is σ = 645744480840. Its totient is φ = 638569541808.

The previous prime is 642157011313. The next prime is 642157011343. The reversal of 642157011323 is 323110751246.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642157011323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642157011313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1793734490 + ... + 1793734847.

It is an arithmetic number, because the mean of its divisors is an integer number (161436120210).

Almost surely, 2^642157011323 is an apocalyptic number.

642157011323 is a deficient number, since it is larger than the sum of its proper divisors (3587469517).

642157011323 is a wasteful number, since it uses less digits than its factorization.

642157011323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3587469516.

The product of its (nonzero) digits is 30240, while the sum is 35.

Adding to 642157011323 its reverse (323110751246), we get a palindrome (965267762569).

The spelling of 642157011323 in words is "six hundred forty-two billion, one hundred fifty-seven million, eleven thousand, three hundred twenty-three".