21046847 has 2 divisors, whose sum is σ = 21046848. Its totient is φ = 21046846.

The previous prime is 21046841. The next prime is 21046859. The reversal of 21046847 is 74864012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21046847 - 2⁶ = 21046783 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21046841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10523423 + 10523424.

It is an arithmetic number, because the mean of its divisors is an integer number (10523424).

Almost surely, 2^21046847 is an apocalyptic number.

21046847 is a deficient number, since it is larger than the sum of its proper divisors (1).

21046847 is an equidigital number, since it uses as much as digits as its factorization.

21046847 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10752, while the sum is 32.

The square root of 21046847 is about 4587.6842742281. The cubic root of 21046847 is about 276.0974197510.

The spelling of 21046847 in words is "twenty-one million, forty-six thousand, eight hundred forty-seven".