1628990989 has 8 divisors (see below), whose sum is σ = 1635116000. Its totient is φ = 1622878416.

The previous prime is 1628990963. The next prime is 1628990999. The reversal of 1628990989 is 9890998261.

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 1628990989 - 2⁹ = 1628990477 is a prime.

It is a super-2 number, since 2×1628990989² = 5307223284486396242, 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 (1628990959) 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, 318319 + ... + 323395.

It is an arithmetic number, because the mean of its divisors is an integer number (204389500).

Almost surely, 2^1628990989 is an apocalyptic number.

It is an amenable number.

1628990989 is a deficient number, since it is larger than the sum of its proper divisors (6125011).

1628990989 is an equidigital number, since it uses as much as digits as its factorization.

1628990989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6219.

The product of its (nonzero) digits is 5038848, while the sum is 61.

The square root of 1628990989 is about 40360.7605106742. The cubic root of 1628990989 is about 1176.6290340008.

The spelling of 1628990989 in words is "one billion, six hundred twenty-eight million, nine hundred ninety thousand, nine hundred eighty-nine".