20355890 has 16 divisors (see below), whose sum is σ = 36998208. Its totient is φ = 8062896.

The previous prime is 20355889. The next prime is 20355893. The reversal of 20355890 is 9855302.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20355893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8852 + ... + 10911.

It is an arithmetic number, because the mean of its divisors is an integer number (2312388).

Almost surely, 2^20355890 is an apocalyptic number.

20355890 is a deficient number, since it is larger than the sum of its proper divisors (16642318).

20355890 is a wasteful number, since it uses less digits than its factorization.

20355890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19873.

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 20355890 is about 4511.7502147171. The cubic root of 20355890 is about 273.0423617215.

The spelling of 20355890 in words is "twenty million, three hundred fifty-five thousand, eight hundred ninety".