20981045 has 8 divisors (see below), whose sum is σ = 25329024. Its totient is φ = 16683664.

The previous prime is 20981041. The next prime is 20981047. The reversal of 20981045 is 54018902.

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

It is a cyclic number.

It is not a de Polignac number, because 20981045 - 2² = 20981041 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20980999 and 20981017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20981041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11729 + ... + 13398.

It is an arithmetic number, because the mean of its divisors is an integer number (3166128).

Almost surely, 2^20981045 is an apocalyptic number.

It is an amenable number.

20981045 is a deficient number, since it is larger than the sum of its proper divisors (4347979).

20981045 is a wasteful number, since it uses less digits than its factorization.

20981045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25299.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 20981045 is about 4580.5070680002. The cubic root of 20981045 is about 275.8093840668.

Adding to 20981045 its reverse (54018902), we get a palindrome (74999947).

The spelling of 20981045 in words is "twenty million, nine hundred eighty-one thousand, forty-five".