20818994 has 8 divisors (see below), whose sum is σ = 35689728. Its totient is φ = 8922420.

The previous prime is 20818981. The next prime is 20818997. The reversal of 20818994 is 49981802.

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

It is a super-2 number, since 2×20818994² = 866861022344072, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20818997) 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 3 ways as a sum of consecutive naturals, for example, 743522 + ... + 743549.

It is an arithmetic number, because the mean of its divisors is an integer number (4461216).

Almost surely, 2^20818994 is an apocalyptic number.

20818994 is a deficient number, since it is larger than the sum of its proper divisors (14870734).

20818994 is a wasteful number, since it uses less digits than its factorization.

20818994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1487080.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 20818994 is about 4562.7835802282. The cubic root of 20818994 is about 275.0974596712.

It can be divided in two parts, 20818 and 994, that added together give a palindrome (21812).

The spelling of 20818994 in words is "twenty million, eight hundred eighteen thousand, nine hundred ninety-four".