21333525 has 12 divisors (see below), whose sum is σ = 35271552. Its totient is φ = 11377840.

The previous prime is 21333511. The next prime is 21333539. The reversal of 21333525 is 52533312.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21333511) and next prime (21333539).

It is not a de Polignac number, because 21333525 - 2⁴ = 21333509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21333495 and 21333504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 142149 + ... + 142298.

It is an arithmetic number, because the mean of its divisors is an integer number (2939296).

Almost surely, 2^21333525 is an apocalyptic number.

21333525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21333525 is a deficient number, since it is larger than the sum of its proper divisors (13938027).

21333525 is a wasteful number, since it uses less digits than its factorization.

21333525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284460 (or 284455 counting only the distinct ones).

The product of its digits is 2700, while the sum is 24.

The square root of 21333525 is about 4618.8229019957. The cubic root of 21333525 is about 277.3453403268.

Adding to 21333525 its reverse (52533312), we get a palindrome (73866837).

The spelling of 21333525 in words is "twenty-one million, three hundred thirty-three thousand, five hundred twenty-five".