21374543 has 2 divisors, whose sum is σ = 21374544. Its totient is φ = 21374542.

The previous prime is 21374513. The next prime is 21374597. The reversal of 21374543 is 34547312.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21374543 - 2¹⁴ = 21358159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21374513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10687271 + 10687272.

It is an arithmetic number, because the mean of its divisors is an integer number (10687272).

Almost surely, 2^21374543 is an apocalyptic number.

21374543 is a deficient number, since it is larger than the sum of its proper divisors (1).

21374543 is an equidigital number, since it uses as much as digits as its factorization.

21374543 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10080, while the sum is 29.

The square root of 21374543 is about 4623.2610785029. The cubic root of 21374543 is about 277.5229772928.

The spelling of 21374543 in words is "twenty-one million, three hundred seventy-four thousand, five hundred forty-three".