21122553 has 8 divisors (see below), whose sum is σ = 28268416. Its totient is φ = 14029200.

The previous prime is 21122473. The next prime is 21122561. The reversal of 21122553 is 35522112.

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

It is not a de Polignac number, because 21122553 - 2¹³ = 21114361 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21192553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12178 + ... + 13803.

It is an arithmetic number, because the mean of its divisors is an integer number (3533552).

Almost surely, 2^21122553 is an apocalyptic number.

It is an amenable number.

21122553 is a deficient number, since it is larger than the sum of its proper divisors (7145863).

21122553 is a wasteful number, since it uses less digits than its factorization.

21122553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26255.

The product of its digits is 600, while the sum is 21.

The square root of 21122553 is about 4595.9278714967. The cubic root of 21122553 is about 276.4280665740.

Adding to 21122553 its reverse (35522112), we get a palindrome (56644665).

The spelling of 21122553 in words is "twenty-one million, one hundred twenty-two thousand, five hundred fifty-three".