21013224121 has 4 divisors (see below), whose sum is σ = 21173630544. Its totient is φ = 20852817700.

The previous prime is 21013224103. The next prime is 21013224139. The reversal of 21013224121 is 12142231012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (21013224103) and next prime (21013224139).

It is a cyclic number.

It is not a de Polignac number, because 21013224121 - 2²³ = 21004835513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21013224151) 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 3 ways as a sum of consecutive naturals, for example, 80203015 + ... + 80203276.

It is an arithmetic number, because the mean of its divisors is an integer number (5293407636).

Almost surely, 2^21013224121 is an apocalyptic number.

It is an amenable number.

21013224121 is a deficient number, since it is larger than the sum of its proper divisors (160406423).

21013224121 is a wasteful number, since it uses less digits than its factorization.

21013224121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160406422.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21013224121 its reverse (12142231012), we get a palindrome (33155455133).

The spelling of 21013224121 in words is "twenty-one billion, thirteen million, two hundred twenty-four thousand, one hundred twenty-one".