20591118 has 64 divisors (see below), whose sum is σ = 48729600. Its totient is φ = 6431040.

The previous prime is 20591111. The next prime is 20591119. The reversal of 20591118 is 81119502.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 20591091 and 20591100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20591111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 73138 + ... + 73418.

It is an arithmetic number, because the mean of its divisors is an integer number (761400).

Almost surely, 2^20591118 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20591118, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24364800).

20591118 is an abundant number, since it is smaller than the sum of its proper divisors (28138482).

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

20591118 is a wasteful number, since it uses less digits than its factorization.

20591118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 374 (or 368 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 27.

The square root of 20591118 is about 4537.7437124633. The cubic root of 20591118 is about 274.0900746356.

The spelling of 20591118 in words is "twenty million, five hundred ninety-one thousand, one hundred eighteen".