20918073 has 16 divisors (see below), whose sum is σ = 30511872. Its totient is φ = 12642000.

The previous prime is 20918071. The next prime is 20918083. The reversal of 20918073 is 37081902.

It is a happy number.

It is not a de Polignac number, because 20918073 - 2¹ = 20918071 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20918073.

It is not an unprimeable number, because it can be changed into a prime (20918071) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15558 + ... + 16848.

It is an arithmetic number, because the mean of its divisors is an integer number (1906992).

Almost surely, 2^20918073 is an apocalyptic number.

It is an amenable number.

20918073 is a deficient number, since it is larger than the sum of its proper divisors (9593799).

20918073 is a wasteful number, since it uses less digits than its factorization.

20918073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1796.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 20918073 is about 4573.6279909936. The cubic root of 20918073 is about 275.5331716761.

Adding to 20918073 its reverse (37081902), we get a palindrome (57999975).

The spelling of 20918073 in words is "twenty million, nine hundred eighteen thousand, seventy-three".