21141224021 has 8 divisors (see below), whose sum is σ = 22989821400. Its totient is φ = 19359848448.

The previous prime is 21141224017. The next prime is 21141224047. The reversal of 21141224021 is 12042214112.

It can be written as a sum of positive squares in 4 ways, for example, as 12524743396 + 8616480625 = 111914^2 + 92825^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21141224021 - 2² = 21141224017 is a prime.

It is a super-2 number, since 2×21141224021² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21141223984 and 21141224002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21141224081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16804796 + ... + 16806053.

It is an arithmetic number, because the mean of its divisors is an integer number (2873727675).

Almost surely, 2^21141224021 is an apocalyptic number.

It is an amenable number.

21141224021 is a deficient number, since it is larger than the sum of its proper divisors (1848597379).

21141224021 is a wasteful number, since it uses less digits than its factorization.

21141224021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33610903.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21141224021 its reverse (12042214112), we get a palindrome (33183438133).

Subtracting from 21141224021 its reverse (12042214112), we obtain a palindrome (9099009909).

The spelling of 21141224021 in words is "twenty-one billion, one hundred forty-one million, two hundred twenty-four thousand, twenty-one".