428247 has 20 divisors (see below), whose sum is σ = 679536. Its totient is φ = 267840.

The previous prime is 428231. The next prime is 428249. The reversal of 428247 is 742824.

It is not a de Polignac number, because 428247 - 2⁴ = 428231 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

428247 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 428247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (428249) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1222 + ... + 1532.

2⁴²⁸²⁴⁷ is an apocalyptic number.

428247 is a deficient number, since it is larger than the sum of its proper divisors (251289).

428247 is a wasteful number, since it uses less digits than its factorization.

428247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340 (or 331 counting only the distinct ones).

The product of its digits is 3584, while the sum is 27.

The square root of 428247 is about 654.4058373823. The cubic root of 428247 is about 75.3757147033.

The spelling of 428247 in words is "four hundred twenty-eight thousand, two hundred forty-seven".