20981086 has 8 divisors (see below), whose sum is σ = 35967600. Its totient is φ = 8991888.

The previous prime is 20981069. The next prime is 20981089. The reversal of 20981086 is 68018902.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20981089) 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, 749311 + ... + 749338.

It is an arithmetic number, because the mean of its divisors is an integer number (4495950).

Almost surely, 2^20981086 is an apocalyptic number.

20981086 is a deficient number, since it is larger than the sum of its proper divisors (14986514).

20981086 is a wasteful number, since it uses less digits than its factorization.

20981086 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1498658.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 20981086 is about 4580.5115434851. The cubic root of 20981086 is about 275.8095637238.

Adding to 20981086 its reverse (68018902), we get a palindrome (88999988).

The spelling of 20981086 in words is "twenty million, nine hundred eighty-one thousand, eighty-six".