20990086 has 16 divisors (see below), whose sum is σ = 34017984. Its totient is φ = 9656064.

The previous prime is 20990071. The next prime is 20990111. The reversal of 20990086 is 68009902.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8035 + ... + 10321.

It is an arithmetic number, because the mean of its divisors is an integer number (2126124).

Almost surely, 2^20990086 is an apocalyptic number.

20990086 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

20990086 is a deficient number, since it is larger than the sum of its proper divisors (13027898).

20990086 is a wasteful number, since it uses less digits than its factorization.

20990086 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2655.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 20990086 is about 4581.4938611767. The cubic root of 20990086 is about 275.8489949720.

Adding to 20990086 its reverse (68009902), we get a palindrome (88999988).

The spelling of 20990086 in words is "twenty million, nine hundred ninety thousand, eighty-six".