20783489 has 4 divisors (see below), whose sum is σ = 20921280. Its totient is φ = 20645700.

The previous prime is 20783479. The next prime is 20783509. The reversal of 20783489 is 98438702.

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 a cyclic number.

It is not a de Polignac number, because 20783489 - 2¹⁶ = 20717953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20783479) 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, 68669 + ... + 68970.

It is an arithmetic number, because the mean of its divisors is an integer number (5230320).

Almost surely, 2^20783489 is an apocalyptic number.

It is an amenable number.

20783489 is a deficient number, since it is larger than the sum of its proper divisors (137791).

20783489 is a wasteful number, since it uses less digits than its factorization.

20783489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137790.

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 20783489 is about 4558.8912029133. The cubic root of 20783489 is about 274.9409856837.

The spelling of 20783489 in words is "twenty million, seven hundred eighty-three thousand, four hundred eighty-nine".