21434745 has 16 divisors (see below), whose sum is σ = 34428672. Its totient is φ = 11387520.

The previous prime is 21434731. The next prime is 21434747. The reversal of 21434745 is 54743412.

It is not a de Polignac number, because 21434745 - 2⁶ = 21434681 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (21434747) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1429 + ... + 6701.

It is an arithmetic number, because the mean of its divisors is an integer number (2151792).

Almost surely, 2^21434745 is an apocalyptic number.

It is an amenable number.

21434745 is a deficient number, since it is larger than the sum of its proper divisors (12993927).

21434745 is a wasteful number, since it uses less digits than its factorization.

21434745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5552.

The product of its digits is 13440, while the sum is 30.

The square root of 21434745 is about 4629.7672727687. The cubic root of 21434745 is about 277.7832834761.

The spelling of 21434745 in words is "twenty-one million, four hundred thirty-four thousand, seven hundred forty-five".