21420313234 has 16 divisors (see below), whose sum is σ = 32203987200. Its totient is φ = 10685669904.

The previous prime is 21420313223. The next prime is 21420313237. The reversal of 21420313234 is 43231302412.

It is a junction number, because it is equal to n+sod(n) for n = 21420313199 and 21420313208.

It is not an unprimeable number, because it can be changed into a prime (21420313237) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4055007 + ... + 4060285.

It is an arithmetic number, because the mean of its divisors is an integer number (2012749200).

Almost surely, 2^21420313234 is an apocalyptic number.

21420313234 is a deficient number, since it is larger than the sum of its proper divisors (10783673966).

21420313234 is a wasteful number, since it uses less digits than its factorization.

21420313234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9537.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21420313234 its reverse (43231302412), we get a palindrome (64651615646).

The spelling of 21420313234 in words is "twenty-one billion, four hundred twenty million, three hundred thirteen thousand, two hundred thirty-four".