20503689 has 4 divisors (see below), whose sum is σ = 27338256. Its totient is φ = 13669124.

The previous prime is 20503687. The next prime is 20503697. The reversal of 20503689 is 98630502.

It is a happy number.

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 20503689 - 2¹ = 20503687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20503687) 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, 3417279 + ... + 3417284.

It is an arithmetic number, because the mean of its divisors is an integer number (6834564).

Almost surely, 2^20503689 is an apocalyptic number.

It is an amenable number.

20503689 is a deficient number, since it is larger than the sum of its proper divisors (6834567).

20503689 is an equidigital number, since it uses as much as digits as its factorization.

20503689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6834566.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 20503689 is about 4528.0999326428. The cubic root of 20503689 is about 273.7015994161.

The spelling of 20503689 in words is "twenty million, five hundred three thousand, six hundred eighty-nine".