21458034 has 80 divisors (see below), whose sum is σ = 54153792. Its totient is φ = 6301152.

The previous prime is 21458033. The next prime is 21458069. The reversal of 21458034 is 43085412.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21457989 and 21458007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21458033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 48217 + ... + 48659.

Almost surely, 2^21458034 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21458034, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27076896).

21458034 is an abundant number, since it is smaller than the sum of its proper divisors (32695758).

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

21458034 is a wasteful number, since it uses less digits than its factorization.

21458034 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 493 (or 484 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 21458034 is about 4632.2817271837. The cubic root of 21458034 is about 277.8838515541.

The spelling of 21458034 in words is "twenty-one million, four hundred fifty-eight thousand, thirty-four".