628862881 has 4 divisors (see below), whose sum is σ = 628967700. Its totient is φ = 628758064.

The previous prime is 628862873. The next prime is 628862891. The reversal of 628862881 is 188268826.

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 164891281 + 463971600 = 12841^2 + 21540^2 .

It is a cyclic number.

It is not a de Polignac number, because 628862881 - 2³ = 628862873 is a prime.

It is a super-2 number, since 2×628862881² = 790937046199240322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (628862891) 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, 42826 + ... + 55603.

It is an arithmetic number, because the mean of its divisors is an integer number (157241925).

Almost surely, 2^628862881 is an apocalyptic number.

It is an amenable number.

628862881 is a deficient number, since it is larger than the sum of its proper divisors (104819).

628862881 is an equidigital number, since it uses as much as digits as its factorization.

628862881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104818.

The product of its digits is 589824, while the sum is 49.

The square root of 628862881 is about 25077.1386126886. The cubic root of 628862881 is about 856.7458057637.

It can be divided in two parts, 6288 and 62881, that added together give a square (69169 = 263²).

The spelling of 628862881 in words is "six hundred twenty-eight million, eight hundred sixty-two thousand, eight hundred eighty-one".