20993118 has 8 divisors (see below), whose sum is σ = 41986248. Its totient is φ = 6997704.

The previous prime is 20993111. The next prime is 20993123. The reversal of 20993118 is 81139902.

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

20993118 is an admirable number.

It is a super-2 number, since 2×20993118² = 881422006723848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20993111) 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, 1749421 + ... + 1749432.

It is an arithmetic number, because the mean of its divisors is an integer number (5248281).

Almost surely, 2^20993118 is an apocalyptic number.

20993118 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20993118 is a wasteful number, since it uses less digits than its factorization.

20993118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3498858.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 20993118 is about 4581.8247456663. The cubic root of 20993118 is about 275.8622763831.

The spelling of 20993118 in words is "twenty million, nine hundred ninety-three thousand, one hundred eighteen".