20501090 has 8 divisors (see below), whose sum is σ = 36901980. Its totient is φ = 8200432.

The previous prime is 20501069. The next prime is 20501123. The reversal of 20501090 is 9010502.

It can be written as a sum of positive squares in 2 ways, for example, as 18515809 + 1985281 = 4303^2 + 1409^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1025045 + ... + 1025064.

Almost surely, 2^20501090 is an apocalyptic number.

20501090 is a deficient number, since it is larger than the sum of its proper divisors (16400890).

20501090 is a wasteful number, since it uses less digits than its factorization.

20501090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2050116.

The product of its (nonzero) digits is 90, while the sum is 17.

The square root of 20501090 is about 4527.8129378321. The cubic root of 20501090 is about 273.6900343344.

Adding to 20501090 its reverse (9010502), we get a palindrome (29511592).

The spelling of 20501090 in words is "twenty million, five hundred one thousand, ninety".