21243002342 has 4 divisors (see below), whose sum is σ = 31864503516. Its totient is φ = 10621501170.

The previous prime is 21243002257. The next prime is 21243002359. The reversal of 21243002342 is 24320034212.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5310750584 + ... + 5310750587.

It is an arithmetic number, because the mean of its divisors is an integer number (7966125879).

Almost surely, 2^21243002342 is an apocalyptic number.

21243002342 is a deficient number, since it is larger than the sum of its proper divisors (10621501174).

21243002342 is a wasteful number, since it uses less digits than its factorization.

21243002342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10621501173.

The product of its (nonzero) digits is 2304, while the sum is 23.

Adding to 21243002342 its reverse (24320034212), we get a palindrome (45563036554).

The spelling of 21243002342 in words is "twenty-one billion, two hundred forty-three million, two thousand, three hundred forty-two".