21325458 has 64 divisors (see below), whose sum is σ = 54927360. Its totient is φ = 5356800.

The previous prime is 21325457. The next prime is 21325471. The reversal of 21325458 is 85452312.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21325457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13578 + ... + 15066.

It is an arithmetic number, because the mean of its divisors is an integer number (858240).

Almost surely, 2^21325458 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21325458, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27463680).

21325458 is an abundant number, since it is smaller than the sum of its proper divisors (33601902).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21325458 is a wasteful number, since it uses less digits than its factorization.

21325458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1543.

The product of its digits is 9600, while the sum is 30.

The square root of 21325458 is about 4617.9495449821. The cubic root of 21325458 is about 277.3103777202.

It can be divided in two parts, 213254 and 58, that added together give a palindrome (213312).

The spelling of 21325458 in words is "twenty-one million, three hundred twenty-five thousand, four hundred fifty-eight".