21312220133 has 16 divisors (see below), whose sum is σ = 22058942976. Its totient is φ = 20579495040.

The previous prime is 21312220087. The next prime is 21312220183. The reversal of 21312220133 is 33102221312.

It is a cyclic number.

It is not a de Polignac number, because 21312220133 - 2³⁴ = 4132350949 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 (21312220183) 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, 1878548 + ... + 1889858.

It is an arithmetic number, because the mean of its divisors is an integer number (1378683936).

Almost surely, 2^21312220133 is an apocalyptic number.

It is an amenable number.

21312220133 is a deficient number, since it is larger than the sum of its proper divisors (746722843).

21312220133 is a wasteful number, since it uses less digits than its factorization.

21312220133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11924.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21312220133 its reverse (33102221312), we get a palindrome (54414441445).

The spelling of 21312220133 in words is "twenty-one billion, three hundred twelve million, two hundred twenty thousand, one hundred thirty-three".