20545131 has 4 divisors (see below), whose sum is σ = 27393512. Its totient is φ = 13696752.

The previous prime is 20545127. The next prime is 20545153. The reversal of 20545131 is 13154502.

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

It is not a de Polignac number, because 20545131 - 2² = 20545127 is a prime.

It is a super-2 number, since 2×20545131² = 844204815614322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20545098 and 20545107.

It is not an unprimeable number, because it can be changed into a prime (20545181) 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, 3424186 + ... + 3424191.

It is an arithmetic number, because the mean of its divisors is an integer number (6848378).

Almost surely, 2^20545131 is an apocalyptic number.

20545131 is a deficient number, since it is larger than the sum of its proper divisors (6848381).

20545131 is an equidigital number, since it uses as much as digits as its factorization.

20545131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6848380.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 20545131 is about 4532.6737142662. The cubic root of 20545131 is about 273.8858769589.

Adding to 20545131 its reverse (13154502), we get a palindrome (33699633).

The spelling of 20545131 in words is "twenty million, five hundred forty-five thousand, one hundred thirty-one".