628690989 has 8 divisors (see below), whose sum is σ = 838965600. Its totient is φ = 418771856.

The previous prime is 628690973. The next prime is 628690999. The reversal of 628690989 is 989096826.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 628690989 - 2⁴ = 628690973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628690999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84714 + ... + 91835.

It is an arithmetic number, because the mean of its divisors is an integer number (104870700).

Almost surely, 2^628690989 is an apocalyptic number.

It is an amenable number.

628690989 is a deficient number, since it is larger than the sum of its proper divisors (210274611).

628690989 is a wasteful number, since it uses less digits than its factorization.

628690989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177739.

The product of its (nonzero) digits is 3359232, while the sum is 57.

The square root of 628690989 is about 25073.7111134351. The cubic root of 628690989 is about 856.6677383108.

The spelling of 628690989 in words is "six hundred twenty-eight million, six hundred ninety thousand, nine hundred eighty-nine".