21145458 has 8 divisors (see below), whose sum is σ = 42290928. Its totient is φ = 7048484.

The previous prime is 21145451. The next prime is 21145469. The reversal of 21145458 is 85454112.

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

21145458 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21145451) 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, 1762116 + ... + 1762127.

It is an arithmetic number, because the mean of its divisors is an integer number (5286366).

Almost surely, 2^21145458 is an apocalyptic number.

21145458 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21145458 is a wasteful number, since it uses less digits than its factorization.

21145458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3524248.

The product of its digits is 6400, while the sum is 30.

The square root of 21145458 is about 4598.4190761608. The cubic root of 21145458 is about 276.5279487176.

The spelling of 21145458 in words is "twenty-one million, one hundred forty-five thousand, four hundred fifty-eight".