20989610 has 8 divisors (see below), whose sum is σ = 37781316. Its totient is φ = 8395840.

The previous prime is 20989609. The next prime is 20989613. The reversal of 20989610 is 1698902.

It can be written as a sum of positive squares in 2 ways, for example, as 18309841 + 2679769 = 4279^2 + 1637^2 .

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

It is not an unprimeable number, because it can be changed into a prime (20989613) 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, 1049471 + ... + 1049490.

Almost surely, 2^20989610 is an apocalyptic number.

20989610 is a deficient number, since it is larger than the sum of its proper divisors (16791706).

20989610 is a wasteful number, since it uses less digits than its factorization.

20989610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2098968.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 20989610 is about 4581.4419127607. The cubic root of 20989610 is about 275.8469097794.

The spelling of 20989610 in words is "twenty million, nine hundred eighty-nine thousand, six hundred ten".