20102989 has 8 divisors (see below), whose sum is σ = 21026880. Its totient is φ = 19183296.

The previous prime is 20102983. The next prime is 20103047. The reversal of 20102989 is 98920102.

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 20102989 - 2⁷ = 20102861 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20102989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20102983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12757 + ... + 14245.

It is an arithmetic number, because the mean of its divisors is an integer number (2628360).

Almost surely, 2^20102989 is an apocalyptic number.

It is an amenable number.

20102989 is a deficient number, since it is larger than the sum of its proper divisors (923891).

20102989 is a wasteful number, since it uses less digits than its factorization.

20102989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2099.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 20102989 is about 4483.6356899284. The cubic root of 20102989 is about 271.9068894465.

The spelling of 20102989 in words is "twenty million, one hundred two thousand, nine hundred eighty-nine".