21312402234 has 32 divisors (see below), whose sum is σ = 43062814080. Its totient is φ = 7031275200.

The previous prime is 21312402173. The next prime is 21312402247. The reversal of 21312402234 is 43220421312.

It is a happy 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 in 15 ways as a sum of consecutive naturals, for example, 598099 + ... + 632729.

It is an arithmetic number, because the mean of its divisors is an integer number (1345712940).

Almost surely, 2^21312402234 is an apocalyptic number.

21312402234 is an abundant number, since it is smaller than the sum of its proper divisors (21750411846).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21312402234 is a wasteful number, since it uses less digits than its factorization.

21312402234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35686.

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21312402234 its reverse (43220421312), we get a palindrome (64532823546).

The spelling of 21312402234 in words is "twenty-one billion, three hundred twelve million, four hundred two thousand, two hundred thirty-four".