21021120124 has 12 divisors (see below), whose sum is σ = 37481054184. Its totient is φ = 10312247504.

The previous prime is 21021120103. The next prime is 21021120149. The reversal of 21021120124 is 42102112012.

It is a junction number, because it is equal to n+sod(n) for n = 21021120098 and 21021120107.

It is a congruent number.

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, 49577902 + ... + 49578325.

It is an arithmetic number, because the mean of its divisors is an integer number (3123421182).

Almost surely, 2^21021120124 is an apocalyptic number.

It is an amenable number.

21021120124 is a deficient number, since it is larger than the sum of its proper divisors (16459934060).

21021120124 is a wasteful number, since it uses less digits than its factorization.

21021120124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99156284 (or 99156282 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21021120124 its reverse (42102112012), we get a palindrome (63123232136).

It can be divided in two parts, 2102112012 and 4, that multiplied together give a palindrome (8408448048).

The spelling of 21021120124 in words is "twenty-one billion, twenty-one million, one hundred twenty thousand, one hundred twenty-four".