21074843 has 2 divisors, whose sum is σ = 21074844. Its totient is φ = 21074842.

The previous prime is 21074813. The next prime is 21074897. The reversal of 21074843 is 34847012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21074843 - 2⁸ = 21074587 is a prime.

It is not a weakly prime, because it can be changed into another prime (21074803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10537421 + 10537422.

It is an arithmetic number, because the mean of its divisors is an integer number (10537422).

Almost surely, 2^21074843 is an apocalyptic number.

21074843 is a deficient number, since it is larger than the sum of its proper divisors (1).

21074843 is an equidigital number, since it uses as much as digits as its factorization.

21074843 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 21074843 is about 4590.7344728268. The cubic root of 21074843 is about 276.2197848514.

The spelling of 21074843 in words is "twenty-one million, seventy-four thousand, eight hundred forty-three".