21121410021 has 24 divisors (see below), whose sum is σ = 29736105120. Its totient is φ = 13333551264.

The previous prime is 21121410019. The next prime is 21121410031. The reversal of 21121410021 is 12001412112.

It is not a de Polignac number, because 21121410021 - 2¹ = 21121410019 is a prime.

It is a super-2 number, since 2×21121410021² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121410031) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3595875 + ... + 3601743.

It is an arithmetic number, because the mean of its divisors is an integer number (1239004380).

Almost surely, 2^21121410021 is an apocalyptic number.

It is an amenable number.

21121410021 is a deficient number, since it is larger than the sum of its proper divisors (8614695099).

21121410021 is a wasteful number, since it uses less digits than its factorization.

21121410021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9233 (or 9214 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21121410021 its reverse (12001412112), we get a palindrome (33122822133).

The spelling of 21121410021 in words is "twenty-one billion, one hundred twenty-one million, four hundred ten thousand, twenty-one".