21304212345 has 48 divisors (see below), whose sum is σ = 39790859472. Its totient is φ = 10482163200.

The previous prime is 21304212317. The next prime is 21304212353. The reversal of 21304212345 is 54321240312.

21304212345 is a `hidden beast` number, since 2 + 1 + 3 + 0 + 421 + 234 + 5 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 11350558521 + 9953653824 = 106539^2 + 99768^2 .

It is not a de Polignac number, because 21304212345 - 2⁵ = 21304212313 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1102507 + ... + 1121663.

It is an arithmetic number, because the mean of its divisors is an integer number (828976239).

Almost surely, 2^21304212345 is an apocalyptic number.

It is an amenable number.

21304212345 is a deficient number, since it is larger than the sum of its proper divisors (18486647127).

21304212345 is a wasteful number, since it uses less digits than its factorization.

21304212345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21082 (or 21079 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

Adding to 21304212345 its reverse (54321240312), we get a palindrome (75625452657).

The spelling of 21304212345 in words is "twenty-one billion, three hundred four million, two hundred twelve thousand, three hundred forty-five".