21225511111 has 8 divisors (see below), whose sum is σ = 24315349664. Its totient is φ = 18150078240.

The previous prime is 21225511103. The next prime is 21225511129. The reversal of 21225511111 is 11111552212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21225511111 - 2³ = 21225511103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21225511511) 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 7 ways as a sum of consecutive naturals, for example, 3598260 + ... + 3604153.

It is an arithmetic number, because the mean of its divisors is an integer number (3039418708).

Almost surely, 2^21225511111 is an apocalyptic number.

21225511111 is a deficient number, since it is larger than the sum of its proper divisors (3089838553).

21225511111 is an equidigital number, since it uses as much as digits as its factorization.

21225511111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7202841.

The product of its digits is 200, while the sum is 22.

The spelling of 21225511111 in words is "twenty-one billion, two hundred twenty-five million, five hundred eleven thousand, one hundred eleven".