20540871 has 20 divisors (see below), whose sum is σ = 33046552. Its totient is φ = 12639888.

The previous prime is 20540851. The next prime is 20540873. The reversal of 20540871 is 17804502.

It is not a de Polignac number, because 20540871 - 2¹¹ = 20538823 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20540873) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8701 + ... + 10806.

Almost surely, 2^20540871 is an apocalyptic number.

20540871 is a deficient number, since it is larger than the sum of its proper divisors (12505681).

20540871 is a wasteful number, since it uses less digits than its factorization.

20540871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19532 (or 19523 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 20540871 is about 4532.2037685876. The cubic root of 20540871 is about 273.8669457178.

The spelling of 20540871 in words is "twenty million, five hundred forty thousand, eight hundred seventy-one".