421847 has 2 divisors, whose sum is σ = 421848. Its totient is φ = 421846.

The previous prime is 421831. The next prime is 421891. The reversal of 421847 is 748124.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 421847 - 2⁴ = 421831 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 (421807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210923 + 210924.

It is an arithmetic number, because the mean of its divisors is an integer number (210924).

2⁴²¹⁸⁴⁷ is an apocalyptic number.

421847 is a deficient number, since it is larger than the sum of its proper divisors (1).

421847 is an equidigital number, since it uses as much as digits as its factorization.

421847 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1792, while the sum is 26.

The square root of 421847 is about 649.4974980706. The cubic root of 421847 is about 74.9983407040.

Subtracting from 421847 its sum of digits (26), we obtain a triangular number (421821 = T₉₁₈).

The spelling of 421847 in words is "four hundred twenty-one thousand, eight hundred forty-seven".