21234312254 has 4 divisors (see below), whose sum is σ = 31851468384. Its totient is φ = 10617156126.

The previous prime is 21234312233. The next prime is 21234312263. The reversal of 21234312254 is 45221343212.

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

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5308578062 + ... + 5308578065.

It is an arithmetic number, because the mean of its divisors is an integer number (7962867096).

Almost surely, 2^21234312254 is an apocalyptic number.

21234312254 is a deficient number, since it is larger than the sum of its proper divisors (10617156130).

21234312254 is a wasteful number, since it uses less digits than its factorization.

21234312254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10617156129.

The product of its digits is 11520, while the sum is 29.

Adding to 21234312254 its reverse (45221343212), we get a palindrome (66455655466).

The spelling of 21234312254 in words is "twenty-one billion, two hundred thirty-four million, three hundred twelve thousand, two hundred fifty-four".