628231385 has 4 divisors (see below), whose sum is σ = 753877668. Its totient is φ = 502585104.

The previous prime is 628231349. The next prime is 628231391. The reversal of 628231385 is 583132826.

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

It can be written as a sum of positive squares in 2 ways, for example, as 125171344 + 503060041 = 11188^2 + 22429^2 .

It is a cyclic number.

It is not a de Polignac number, because 628231385 - 2⁸ = 628231129 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62823134 + ... + 62823143.

It is an arithmetic number, because the mean of its divisors is an integer number (188469417).

Almost surely, 2^628231385 is an apocalyptic number.

It is an amenable number.

628231385 is a deficient number, since it is larger than the sum of its proper divisors (125646283).

628231385 is a wasteful number, since it uses less digits than its factorization.

628231385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125646282.

The product of its digits is 69120, while the sum is 38.

The square root of 628231385 is about 25064.5443804590. The cubic root of 628231385 is about 856.4589320186.

The spelling of 628231385 in words is "six hundred twenty-eight million, two hundred thirty-one thousand, three hundred eighty-five".