428028749 has 4 divisors (see below), whose sum is σ = 441836160. Its totient is φ = 414221340.

The previous prime is 428028743. The next prime is 428028779. The reversal of 428028749 is 947820824.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 428028749 - 2²⁰ = 426980173 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 (428028743) 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, 6903659 + ... + 6903720.

It is an arithmetic number, because the mean of its divisors is an integer number (110459040).

Almost surely, 2^428028749 is an apocalyptic number.

It is an amenable number.

428028749 is a deficient number, since it is larger than the sum of its proper divisors (13807411).

428028749 is a wasteful number, since it uses less digits than its factorization.

428028749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13807410.

The product of its (nonzero) digits is 258048, while the sum is 44.

The square root of 428028749 is about 20688.8556715929. The cubic root of 428028749 is about 753.6290774796.

The spelling of 428028749 in words is "four hundred twenty-eight million, twenty-eight thousand, seven hundred forty-nine".