21133223511 has 16 divisors (see below), whose sum is σ = 29429692800. Its totient is φ = 13475693088.

The previous prime is 21133223509. The next prime is 21133223513. The reversal of 21133223511 is 11532233112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21133223509) and next prime (21133223513).

It is not a de Polignac number, because 21133223511 - 2¹ = 21133223509 is a prime.

It is a super-2 number, since 2×21133223511² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21133223513) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1606921 + ... + 1620018.

It is an arithmetic number, because the mean of its divisors is an integer number (1839355800).

Almost surely, 2^21133223511 is an apocalyptic number.

21133223511 is a deficient number, since it is larger than the sum of its proper divisors (8296469289).

21133223511 is a wasteful number, since it uses less digits than its factorization.

21133223511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3227038.

The product of its digits is 1080, while the sum is 24.

Adding to 21133223511 its reverse (11532233112), we get a palindrome (32665456623).

The spelling of 21133223511 in words is "twenty-one billion, one hundred thirty-three million, two hundred twenty-three thousand, five hundred eleven".