21124100512 has 24 divisors (see below), whose sum is σ = 41651031492. Its totient is φ = 10546060800.

The previous prime is 21124100489. The next prime is 21124100531. The reversal of 21124100512 is 21500142112.

It can be written as a sum of positive squares in 2 ways, for example, as 21119064976 + 5035536 = 145324^2 + 2244^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21124100512.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 478189 + ... + 520492.

Almost surely, 2^21124100512 is an apocalyptic number.

It is an amenable number.

21124100512 is a deficient number, since it is larger than the sum of its proper divisors (20526930980).

21124100512 is an equidigital number, since it uses as much as digits as its factorization.

21124100512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 999352 (or 999344 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

Adding to 21124100512 its reverse (21500142112), we get a palindrome (42624242624).

The spelling of 21124100512 in words is "twenty-one billion, one hundred twenty-four million, one hundred thousand, five hundred twelve".