20290005 has 36 divisors (see below), whose sum is σ = 37147500. Its totient is φ = 10243584.

The previous prime is 20290001. The next prime is 20290007. The reversal of 20290005 is 50009202.

It can be written as a sum of positive squares in 2 ways, for example, as 7800849 + 12489156 = 2793^2 + 3534^2 .

It is not a de Polignac number, because 20290005 - 2² = 20290001 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20290005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20290001) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 15621 + ... + 16869.

It is an arithmetic number, because the mean of its divisors is an integer number (1031875).

Almost surely, 2^20290005 is an apocalyptic number.

It is an amenable number.

20290005 is a deficient number, since it is larger than the sum of its proper divisors (16857495).

20290005 is a wasteful number, since it uses less digits than its factorization.

20290005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1298 (or 1276 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 20290005 is about 4504.4428068297. The cubic root of 20290005 is about 272.7474619903.

Adding to 20290005 its reverse (50009202), we get a palindrome (70299207).

The spelling of 20290005 in words is "twenty million, two hundred ninety thousand, five".