20408071 has 4 divisors (see below), whose sum is σ = 21482200. Its totient is φ = 19333944.

The previous prime is 20408051. The next prime is 20408077. The reversal of 20408071 is 17080402.

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

It is not a de Polignac number, because 20408071 - 2⁵ = 20408039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20408077) 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, 537036 + ... + 537073.

It is an arithmetic number, because the mean of its divisors is an integer number (5370550).

Almost surely, 2^20408071 is an apocalyptic number.

20408071 is a deficient number, since it is larger than the sum of its proper divisors (1074129).

20408071 is a wasteful number, since it uses less digits than its factorization.

20408071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1074128.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 20408071 is about 4517.5293026166. The cubic root of 20408071 is about 273.2754714258.

Adding to 20408071 its reverse (17080402), we get a palindrome (37488473).

The spelling of 20408071 in words is "twenty million, four hundred eight thousand, seventy-one".