100021121221 has 4 divisors (see below), whose sum is σ = 114309852832. Its totient is φ = 85732389612.

The previous prime is 100021121201. The next prime is 100021121227. The reversal of 100021121221 is 122121120001.

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, and also an emirpimes, since its reverse is a distinct semiprime: 122121120001 = 98561 ⋅1239041.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-100021121221 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100021121227) 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, 7144365795 + ... + 7144365808.

It is an arithmetic number, because the mean of its divisors is an integer number (28577463208).

Almost surely, 2^100021121221 is an apocalyptic number.

It is an amenable number.

100021121221 is a deficient number, since it is larger than the sum of its proper divisors (14288731611).

100021121221 is an equidigital number, since it uses as much as digits as its factorization.

100021121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14288731610.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 100021121221 its reverse (122121120001), we get a palindrome (222142241222).

The spelling of 100021121221 in words is "one hundred billion, twenty-one million, one hundred twenty-one thousand, two hundred twenty-one".