421647 has 4 divisors (see below), whose sum is σ = 562200. Its totient is φ = 281096.

The previous prime is 421643. The next prime is 421657. The reversal of 421647 is 746124.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 421647 - 2² = 421643 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70272 + ... + 70277.

It is an arithmetic number, because the mean of its divisors is an integer number (140550).

2⁴²¹⁶⁴⁷ is an apocalyptic number.

421647 is a deficient number, since it is larger than the sum of its proper divisors (140553).

421647 is a wasteful number, since it uses less digits than its factorization.

421647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140552.

The product of its digits is 1344, while the sum is 24.

The square root of 421647 is about 649.3435146361. The cubic root of 421647 is about 74.9864864542.

The spelling of 421647 in words is "four hundred twenty-one thousand, six hundred forty-seven".