20162181 has 8 divisors (see below), whose sum is σ = 28950880. Its totient is φ = 12407472.

The previous prime is 20162171. The next prime is 20162213. The reversal of 20162181 is 18126102.

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

It is not a de Polignac number, because 20162181 - 2¹⁰ = 20161157 is a prime.

It is a super-2 number, since 2×20162181² = 813027085353522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20162171) 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, 258451 + ... + 258528.

It is an arithmetic number, because the mean of its divisors is an integer number (3618860).

Almost surely, 2^20162181 is an apocalyptic number.

It is an amenable number.

20162181 is a deficient number, since it is larger than the sum of its proper divisors (8788699).

20162181 is a wasteful number, since it uses less digits than its factorization.

20162181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 516995.

The product of its (nonzero) digits is 192, while the sum is 21.

The square root of 20162181 is about 4490.2317312139. The cubic root of 20162181 is about 272.1734989171.

Adding to 20162181 its reverse (18126102), we get a palindrome (38288283).

The spelling of 20162181 in words is "twenty million, one hundred sixty-two thousand, one hundred eighty-one".