21304440434 has 16 divisors (see below), whose sum is σ = 33104941056. Its totient is φ = 10271906400.

The previous prime is 21304440397. The next prime is 21304440473. The reversal of 21304440434 is 43404440312.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21304440397 and 21304440406.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 594002 + ... + 628845.

It is an arithmetic number, because the mean of its divisors is an integer number (2069058816).

Almost surely, 2^21304440434 is an apocalyptic number.

21304440434 is a deficient number, since it is larger than the sum of its proper divisors (11800500622).

21304440434 is a wasteful number, since it uses less digits than its factorization.

21304440434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223161.

The product of its (nonzero) digits is 18432, while the sum is 29.

Adding to 21304440434 its reverse (43404440312), we get a palindrome (64708880746).

The spelling of 21304440434 in words is "twenty-one billion, three hundred four million, four hundred forty thousand, four hundred thirty-four".