428247791 has 4 divisors (see below), whose sum is σ = 436327992. Its totient is φ = 420167592.

The previous prime is 428247773. The next prime is 428247803. The reversal of 428247791 is 197742824.

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 428247791 - 2²⁶ = 361138927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (428247761) 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, 4040021 + ... + 4040126.

It is an arithmetic number, because the mean of its divisors is an integer number (109081998).

Almost surely, 2^428247791 is an apocalyptic number.

428247791 is a deficient number, since it is larger than the sum of its proper divisors (8080201).

428247791 is an equidigital number, since it uses as much as digits as its factorization.

428247791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8080200.

The product of its digits is 225792, while the sum is 44.

The square root of 428247791 is about 20694.1487140689. The cubic root of 428247791 is about 753.7576111117.

The spelling of 428247791 in words is "four hundred twenty-eight million, two hundred forty-seven thousand, seven hundred ninety-one".