21427458 has 16 divisors (see below), whose sum is σ = 46151616. Its totient is φ = 6593040.

The previous prime is 21427457. The next prime is 21427481. The reversal of 21427458 is 85472412.

It is not an unprimeable number, because it can be changed into a prime (21427451) 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 7 ways as a sum of consecutive naturals, for example, 137278 + ... + 137433.

It is an arithmetic number, because the mean of its divisors is an integer number (2884476).

Almost surely, 2^21427458 is an apocalyptic number.

21427458 is an abundant number, since it is smaller than the sum of its proper divisors (24724158).

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

21427458 is a wasteful number, since it uses less digits than its factorization.

21427458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274729.

The product of its digits is 17920, while the sum is 33.

The square root of 21427458 is about 4628.9802332695. The cubic root of 21427458 is about 277.7518013161.

It can be divided in two parts, 214 and 27458, that added together give a palindrome (27672).

The spelling of 21427458 in words is "twenty-one million, four hundred twenty-seven thousand, four hundred fifty-eight".