20540090 has 8 divisors (see below), whose sum is σ = 36972180. Its totient is φ = 8216032.

The previous prime is 20540059. The next prime is 20540099. The reversal of 20540090 is 9004502.

It can be written as a sum of positive squares in 2 ways, for example, as 20349121 + 190969 = 4511^2 + 437^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20540099) 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, 1026995 + ... + 1027014.

Almost surely, 2^20540090 is an apocalyptic number.

20540090 is a deficient number, since it is larger than the sum of its proper divisors (16432090).

20540090 is a wasteful number, since it uses less digits than its factorization.

20540090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2054016.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 20540090 is about 4532.1176065941. The cubic root of 20540090 is about 273.8634747063.

Adding to 20540090 its reverse (9004502), we get a palindrome (29544592).

The spelling of 20540090 in words is "twenty million, five hundred forty thousand, ninety".