21121450001 has 4 divisors (see below), whose sum is σ = 21121772400. Its totient is φ = 21121127604.

The previous prime is 21121449989. The next prime is 21121450043. The reversal of 21121450001 is 10005412112.

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 a cyclic number.

It is not a de Polignac number, because 21121450001 - 2¹⁰ = 21121448977 is a prime.

It is a super-2 number, since 2×21121450001² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21121450901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24011 + ... + 206928.

It is an arithmetic number, because the mean of its divisors is an integer number (5280443100).

Almost surely, 2^21121450001 is an apocalyptic number.

It is an amenable number.

21121450001 is a deficient number, since it is larger than the sum of its proper divisors (322399).

21121450001 is an equidigital number, since it uses as much as digits as its factorization.

21121450001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322398.

The product of its (nonzero) digits is 80, while the sum is 17.

Adding to 21121450001 its reverse (10005412112), we get a palindrome (31126862113).

The spelling of 21121450001 in words is "twenty-one billion, one hundred twenty-one million, four hundred fifty thousand, one".