20170081 has 2 divisors, whose sum is σ = 20170082. Its totient is φ = 20170080.

The previous prime is 20170063. The next prime is 20170121. The reversal of 20170081 is 18007102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19219456 + 950625 = 4384^2 + 975^2 .

It is a cyclic number.

It is not a de Polignac number, because 20170081 - 2⁵ = 20170049 is a prime.

It is a super-2 number, since 2×20170081² = 813664335093122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20170021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10085040 + 10085041.

It is an arithmetic number, because the mean of its divisors is an integer number (10085041).

Almost surely, 2^20170081 is an apocalyptic number.

It is an amenable number.

20170081 is a deficient number, since it is larger than the sum of its proper divisors (1).

20170081 is an equidigital number, since it uses as much as digits as its factorization.

20170081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 19.

The square root of 20170081 is about 4491.1113323987. Note that the first 3 decimals coincide. The cubic root of 20170081 is about 272.2090421928.

Adding to 20170081 its reverse (18007102), we get a palindrome (38177183).

The spelling of 20170081 in words is "twenty million, one hundred seventy thousand, eighty-one".