342123821 has 4 divisors (see below), whose sum is σ = 368441052. Its totient is φ = 315806592.

The previous prime is 342123809. The next prime is 342123863. The reversal of 342123821 is 128321243.

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

It can be written as a sum of positive squares in 2 ways, for example, as 186622921 + 155500900 = 13661^2 + 12470^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-342123821 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 (342123421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13158596 + ... + 13158621.

It is an arithmetic number, because the mean of its divisors is an integer number (92110263).

Almost surely, 2^342123821 is an apocalyptic number.

It is an amenable number.

342123821 is a deficient number, since it is larger than the sum of its proper divisors (26317231).

342123821 is a wasteful number, since it uses less digits than its factorization.

342123821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26317230.

The product of its digits is 2304, while the sum is 26.

The square root of 342123821 is about 18496.5894423810. The cubic root of 342123821 is about 699.4034516227.

The spelling of 342123821 in words is "three hundred forty-two million, one hundred twenty-three thousand, eight hundred twenty-one".