21122221121101 has 4 divisors (see below), whose sum is σ = 22233916969600. Its totient is φ = 20010525272604.

The previous prime is 21122221121083. The next prime is 21122221121129. The reversal of 21122221121101 is 10112112222112.

It is a happy number.

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 21122221121101 - 2²³ = 21122212732493 is a prime.

It is a super-2 number, since 2×21122221121101² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 1111695848479 = 21122221121101 / (2 + 1 + 1 + 2 + 2 + 2 + 2 + 1 + 1 + 2 + 1 + 1 + 0 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122221121201) 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, 555847924221 + ... + 555847924258.

It is an arithmetic number, because the mean of its divisors is an integer number (5558479242400).

Almost surely, 2^{21122221121101} is an apocalyptic number.

It is an amenable number.

21122221121101 is a deficient number, since it is larger than the sum of its proper divisors (1111695848499).

21122221121101 is a wasteful number, since it uses less digits than its factorization.

21122221121101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1111695848498.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21122221121101 its reverse (10112112222112), we get a palindrome (31234333343213).

It can be divided in two parts, 2112222 and 1121101, that added together give a palindrome (3233323).

The spelling of 21122221121101 in words is "twenty-one trillion, one hundred twenty-two billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred one".