21243133234 has 4 divisors (see below), whose sum is σ = 31864699854. Its totient is φ = 10621566616.

The previous prime is 21243133231. The next prime is 21243133271. The reversal of 21243133234 is 43233134212.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 14591915209 + 6651218025 = 120797^2 + 81555^2 .

It is not an unprimeable number, because it can be changed into a prime (21243133231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5310783307 + ... + 5310783310.

Almost surely, 2^21243133234 is an apocalyptic number.

21243133234 is a deficient number, since it is larger than the sum of its proper divisors (10621566620).

21243133234 is a wasteful number, since it uses less digits than its factorization.

21243133234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10621566619.

The product of its digits is 10368, while the sum is 28.

Adding to 21243133234 its reverse (43233134212), we get a palindrome (64476267446).

The spelling of 21243133234 in words is "twenty-one billion, two hundred forty-three million, one hundred thirty-three thousand, two hundred thirty-four".