20503471 has 4 divisors (see below), whose sum is σ = 20528200. Its totient is φ = 20478744.

The previous prime is 20503463. The next prime is 20503481. The reversal of 20503471 is 17430502.

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

It is a cyclic number.

It is not a de Polignac number, because 20503471 - 2³ = 20503463 is a prime.

It is a super-3 number, since 3×20503471³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

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, 11076 + ... + 12793.

It is an arithmetic number, because the mean of its divisors is an integer number (5132050).

Almost surely, 2^20503471 is an apocalyptic number.

20503471 is a deficient number, since it is larger than the sum of its proper divisors (24729).

20503471 is an equidigital number, since it uses as much as digits as its factorization.

20503471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24728.

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 20503471 is about 4528.0758606719. The cubic root of 20503471 is about 273.7006293930.

Adding to 20503471 its reverse (17430502), we get a palindrome (37933973).

The spelling of 20503471 in words is "twenty million, five hundred three thousand, four hundred seventy-one".