21155020222 has 16 divisors (see below), whose sum is σ = 36530465760. Its totient is φ = 9000258048.

The previous prime is 21155020213. The next prime is 21155020259. The reversal of 21155020222 is 22202055112.

It is a junction number, because it is equal to n+sod(n) for n = 21155020193 and 21155020202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5512947 + ... + 5516782.

It is an arithmetic number, because the mean of its divisors is an integer number (2283154110).

Almost surely, 2^21155020222 is an apocalyptic number.

21155020222 is a deficient number, since it is larger than the sum of its proper divisors (15375445538).

21155020222 is a wasteful number, since it uses less digits than its factorization.

21155020222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11029875.

The product of its (nonzero) digits is 800, while the sum is 22.

Adding to 21155020222 its reverse (22202055112), we get a palindrome (43357075334).

The spelling of 21155020222 in words is "twenty-one billion, one hundred fifty-five million, twenty thousand, two hundred twenty-two".