628920813 has 4 divisors (see below), whose sum is σ = 838561088. Its totient is φ = 419280540.

The previous prime is 628920793. The next prime is 628920827. The reversal of 628920813 is 318029826.

It is a happy number.

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 not a de Polignac number, because 628920813 - 2⁶ = 628920749 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 (628920863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104820133 + ... + 104820138.

It is an arithmetic number, because the mean of its divisors is an integer number (209640272).

Almost surely, 2^628920813 is an apocalyptic number.

It is an amenable number.

628920813 is a deficient number, since it is larger than the sum of its proper divisors (209640275).

628920813 is a wasteful number, since it uses less digits than its factorization.

628920813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209640274.

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 628920813 is about 25078.2936620497. The cubic root of 628920813 is about 856.7721132866.

The spelling of 628920813 in words is "six hundred twenty-eight million, nine hundred twenty thousand, eight hundred thirteen".