21124040012 has 24 divisors (see below), whose sum is σ = 37186416960. Its totient is φ = 10499536080.

The previous prime is 21124039997. The next prime is 21124040023. The reversal of 21124040012 is 21004042112.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 436439 + ... + 482417.

It is an arithmetic number, because the mean of its divisors is an integer number (1549434040).

Almost surely, 2^21124040012 is an apocalyptic number.

It is an amenable number.

21124040012 is a deficient number, since it is larger than the sum of its proper divisors (16062376948).

21124040012 is a wasteful number, since it uses less digits than its factorization.

21124040012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46661 (or 46659 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21124040012 its reverse (21004042112), we get a palindrome (42128082124).

The spelling of 21124040012 in words is "twenty-one billion, one hundred twenty-four million, forty thousand, twelve".