21321221242042 has 32 divisors (see below), whose sum is σ = 34152645340800. Its totient is φ = 9947923765248.

The previous prime is 21321221242021. The next prime is 21321221242151. The reversal of 21321221242042 is 24024212212312.

It is a self number, because there is not a number n which added to its sum of digits gives 21321221242042.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 475434 + ... + 6547402.

It is an arithmetic number, because the mean of its divisors is an integer number (1067270166900).

Almost surely, 2^{21321221242042} is an apocalyptic number.

21321221242042 is a deficient number, since it is larger than the sum of its proper divisors (12831424098758).

21321221242042 is a wasteful number, since it uses less digits than its factorization.

21321221242042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6072870.

The product of its (nonzero) digits is 6144, while the sum is 28.

Adding to 21321221242042 its reverse (24024212212312), we get a palindrome (45345433454354).

The spelling of 21321221242042 in words is "twenty-one trillion, three hundred twenty-one billion, two hundred twenty-one million, two hundred forty-two thousand, forty-two".