21522131366 has 8 divisors (see below), whose sum is σ = 33686814384. Its totient is φ = 10293193240.

The previous prime is 21522131357. The next prime is 21522131377. The reversal of 21522131366 is 66313122512.

It is a happy number.

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

It is a super-2 number, since 2×21522131366² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 233936165 + ... + 233936256.

It is an arithmetic number, because the mean of its divisors is an integer number (4210851798).

Almost surely, 2^21522131366 is an apocalyptic number.

21522131366 is a deficient number, since it is larger than the sum of its proper divisors (12164683018).

21522131366 is a wasteful number, since it uses less digits than its factorization.

21522131366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 467872446.

The product of its digits is 12960, while the sum is 32.

Adding to 21522131366 its reverse (66313122512), we get a palindrome (87835253878).

The spelling of 21522131366 in words is "twenty-one billion, five hundred twenty-two million, one hundred thirty-one thousand, three hundred sixty-six".