20162681 has 16 divisors (see below), whose sum is σ = 25239168. Its totient is φ = 15648000.

The previous prime is 20162641. The next prime is 20162717. The reversal of 20162681 is 18626102.

It is a cyclic number.

It is not a de Polignac number, because 20162681 - 2¹⁸ = 19900537 is a prime.

It is a super-2 number, since 2×20162681² = 813067410215522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20162681.

It is not an unprimeable number, because it can be changed into a prime (20162641) 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 15 ways as a sum of consecutive naturals, for example, 30551 + ... + 31203.

It is an arithmetic number, because the mean of its divisors is an integer number (1577448).

Almost surely, 2^20162681 is an apocalyptic number.

It is an amenable number.

20162681 is a deficient number, since it is larger than the sum of its proper divisors (5076487).

20162681 is a wasteful number, since it uses less digits than its factorization.

20162681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1072.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 20162681 is about 4490.2874072825. The cubic root of 20162681 is about 272.1757487667.

Adding to 20162681 its reverse (18626102), we get a palindrome (38788783).

The spelling of 20162681 in words is "twenty million, one hundred sixty-two thousand, six hundred eighty-one".