21121336 has 8 divisors (see below), whose sum is σ = 39602520. Its totient is φ = 10560664.

The previous prime is 21121333. The next prime is 21121349. The reversal of 21121336 is 63312112.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21121336² = 892221668849792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1320076 + ... + 1320091.

It is an arithmetic number, because the mean of its divisors is an integer number (4950315).

Almost surely, 2^21121336 is an apocalyptic number.

It is an amenable number.

21121336 is a deficient number, since it is larger than the sum of its proper divisors (18481184).

21121336 is a wasteful number, since it uses less digits than its factorization.

21121336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2640173 (or 2640169 counting only the distinct ones).

The product of its digits is 216, while the sum is 19.

The square root of 21121336 is about 4595.7954697745. The cubic root of 21121336 is about 276.4227575658.

Adding to 21121336 its reverse (63312112), we get a palindrome (84433448).

The spelling of 21121336 in words is "twenty-one million, one hundred twenty-one thousand, three hundred thirty-six".