21045458 has 8 divisors (see below), whose sum is σ = 36077952. Its totient is φ = 9019476.

The previous prime is 21045457. The next prime is 21045461. The reversal of 21045458 is 85454012.

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

It is a super-2 number, since 2×21045458² = 885822604859528, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21045458.

It is not an unprimeable number, because it can be changed into a prime (21045457) 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, 751610 + ... + 751637.

It is an arithmetic number, because the mean of its divisors is an integer number (4509744).

Almost surely, 2^21045458 is an apocalyptic number.

21045458 is a deficient number, since it is larger than the sum of its proper divisors (15032494).

21045458 is a wasteful number, since it uses less digits than its factorization.

21045458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1503256.

The product of its (nonzero) digits is 6400, while the sum is 29.

The square root of 21045458 is about 4587.5328881655. The cubic root of 21045458 is about 276.0913458760.

It can be divided in two parts, 2 and 1045458, that multiplied together give a square (2090916 = 1446²).

The spelling of 21045458 in words is "twenty-one million, forty-five thousand, four hundred fifty-eight".