21121010224 has 20 divisors (see below), whose sum is σ = 41297391520. Its totient is φ = 10463618880.

The previous prime is 21121010221. The next prime is 21121010269. The reversal of 21121010224 is 42201012112.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 21121010198 and 21121010207.

It is not an unprimeable number, because it can be changed into a prime (21121010221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6053592 + ... + 6057079.

It is an arithmetic number, because the mean of its divisors is an integer number (2064869576).

Almost surely, 2^21121010224 is an apocalyptic number.

It is an amenable number.

21121010224 is a deficient number, since it is larger than the sum of its proper divisors (20176381296).

21121010224 is a wasteful number, since it uses less digits than its factorization.

21121010224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12110788 (or 12110782 counting only the distinct ones).

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

Adding to 21121010224 its reverse (42201012112), we get a palindrome (63322022336).

The spelling of 21121010224 in words is "twenty-one billion, one hundred twenty-one million, ten thousand, two hundred twenty-four".