21092543 has 2 divisors, whose sum is σ = 21092544. Its totient is φ = 21092542.

The previous prime is 21092507. The next prime is 21092549. The reversal of 21092543 is 34529012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21092543 - 2¹⁶ = 21027007 is a prime.

It is a Chen prime.

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

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21092549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10546271 + 10546272.

It is an arithmetic number, because the mean of its divisors is an integer number (10546272).

Almost surely, 2^21092543 is an apocalyptic number.

21092543 is a deficient number, since it is larger than the sum of its proper divisors (1).

21092543 is an equidigital number, since it uses as much as digits as its factorization.

21092543 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 21092543 is about 4592.6618643223. The cubic root of 21092543 is about 276.2970922222.

The spelling of 21092543 in words is "twenty-one million, ninety-two thousand, five hundred forty-three".