20740181 has 32 divisors (see below), whose sum is σ = 27648000. Its totient is φ = 15393840.

The previous prime is 20740177. The next prime is 20740189. The reversal of 20740181 is 18104702.

It is not a de Polignac number, because 20740181 - 2² = 20740177 is a prime.

It is a super-2 number, since 2×20740181² = 860310215825522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20740189) 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 31 ways as a sum of consecutive naturals, for example, 86660 + ... + 86898.

It is an arithmetic number, because the mean of its divisors is an integer number (864000).

Almost surely, 2^20740181 is an apocalyptic number.

It is an amenable number.

20740181 is a deficient number, since it is larger than the sum of its proper divisors (6907819).

20740181 is a wasteful number, since it uses less digits than its factorization.

20740181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 20740181 is about 4554.1388867710. The cubic root of 20740181 is about 274.7498816720.

Adding to 20740181 its reverse (18104702), we get a palindrome (38844883).

The spelling of 20740181 in words is "twenty million, seven hundred forty thousand, one hundred eighty-one".