20503491 has 4 divisors (see below), whose sum is σ = 27337992. Its totient is φ = 13668992.

The previous prime is 20503481. The next prime is 20503501. The reversal of 20503491 is 19430502.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20503481) and next prime (20503501).

It is a cyclic number.

It is not a de Polignac number, because 20503491 - 2⁵ = 20503459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20503481) 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, 3417246 + ... + 3417251.

It is an arithmetic number, because the mean of its divisors is an integer number (6834498).

Almost surely, 2^20503491 is an apocalyptic number.

20503491 is a deficient number, since it is larger than the sum of its proper divisors (6834501).

20503491 is an equidigital number, since it uses as much as digits as its factorization.

20503491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6834500.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 20503491 is about 4528.0780691150. The cubic root of 20503491 is about 273.7007183862.

Adding to 20503491 its reverse (19430502), we get a palindrome (39933993).

The spelling of 20503491 in words is "twenty million, five hundred three thousand, four hundred ninety-one".