21292847 has 2 divisors, whose sum is σ = 21292848. Its totient is φ = 21292846.

The previous prime is 21292837. The next prime is 21292867. The reversal of 21292847 is 74829212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21292847 - 2¹⁸ = 21030703 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 (21292837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10646423 + 10646424.

It is an arithmetic number, because the mean of its divisors is an integer number (10646424).

Almost surely, 2^21292847 is an apocalyptic number.

21292847 is a deficient number, since it is larger than the sum of its proper divisors (1).

21292847 is an equidigital number, since it uses as much as digits as its factorization.

21292847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128, while the sum is 35.

The square root of 21292847 is about 4614.4172979912. The cubic root of 21292847 is about 277.1689507870.

The spelling of 21292847 in words is "twenty-one million, two hundred ninety-two thousand, eight hundred forty-seven".