628764181 has 4 divisors (see below), whose sum is σ = 631924000. Its totient is φ = 625604364.

The previous prime is 628764163. The next prime is 628764197. The reversal of 628764181 is 181467826.

628764181 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 628764181 - 2¹¹ = 628762133 is a prime.

It is a super-2 number, since 2×628764181² = 790688790617201522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628764481) 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, 1579611 + ... + 1580008.

It is an arithmetic number, because the mean of its divisors is an integer number (157981000).

Almost surely, 2^628764181 is an apocalyptic number.

It is an amenable number.

628764181 is a deficient number, since it is larger than the sum of its proper divisors (3159819).

628764181 is a wasteful number, since it uses less digits than its factorization.

628764181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3159818.

The product of its digits is 129024, while the sum is 43.

The square root of 628764181 is about 25075.1706075951. The cubic root of 628764181 is about 856.7009813471.

The spelling of 628764181 in words is "six hundred twenty-eight million, seven hundred sixty-four thousand, one hundred eighty-one".