21253933 has 4 divisors (see below), whose sum is σ = 21330940. Its totient is φ = 21177204.

The previous prime is 21253931. The next prime is 21253937. The reversal of 21253933 is 33935212.

The cubic root of 21253933 is 277.

It is a perfect power (a cube), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 432964 + 20820969 = 658^2 + 4563^2 .

It is not a de Polignac number, because 21253933 - 2¹ = 21253931 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 (21253931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76591 + ... + 76867.

It is an arithmetic number, because the mean of its divisors is an integer number (5332735).

Almost surely, 2^21253933 is an apocalyptic number.

It is an amenable number.

21253933 is a deficient number, since it is larger than the sum of its proper divisors (77007).

21253933 is an frugal number, since it uses more digits than its factorization.

21253933 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 831 (or 277 counting only the distinct ones).

The product of its digits is 4860, while the sum is 28.

The square root of 21253933 is about 4610.1988026548.

It can be divided in two parts, 212 and 53933, that added together give a palindrome (54145).

The spelling of 21253933 in words is "twenty-one million, two hundred fifty-three thousand, nine hundred thirty-three".