21421322511 has 8 divisors (see below), whose sum is σ = 28711302144. Its totient is φ = 14206112280.

The previous prime is 21421322473. The next prime is 21421322519. The reversal of 21421322511 is 11522312412.

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 21421322511 - 2¹¹ = 21421320463 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21421322519) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18691681 + ... + 18692826.

It is an arithmetic number, because the mean of its divisors is an integer number (3588912768).

Almost surely, 2^21421322511 is an apocalyptic number.

21421322511 is a deficient number, since it is larger than the sum of its proper divisors (7289979633).

21421322511 is a wasteful number, since it uses less digits than its factorization.

21421322511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37384701.

The product of its digits is 960, while the sum is 24.

Adding to 21421322511 its reverse (11522312412), we get a palindrome (32943634923).

The spelling of 21421322511 in words is "twenty-one billion, four hundred twenty-one million, three hundred twenty-two thousand, five hundred eleven".