20490718 has 4 divisors (see below), whose sum is σ = 30736080. Its totient is φ = 10245358.

The previous prime is 20490713. The next prime is 20490727. The reversal of 20490718 is 81709402.

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

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 20490718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20490713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5122678 + ... + 5122681.

It is an arithmetic number, because the mean of its divisors is an integer number (7684020).

Almost surely, 2^20490718 is an apocalyptic number.

20490718 is a deficient number, since it is larger than the sum of its proper divisors (10245362).

20490718 is a wasteful number, since it uses less digits than its factorization.

20490718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10245361.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 20490718 is about 4526.6674275895. The cubic root of 20490718 is about 273.6438710671.

The spelling of 20490718 in words is "twenty million, four hundred ninety thousand, seven hundred eighteen".