401000000081 has 2 divisors, whose sum is σ = 401000000082. Its totient is φ = 401000000080.

The previous prime is 401000000077. The next prime is 401000000123. The reversal of 401000000081 is 180000000104.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 370626481681 + 30373518400 = 608791^2 + 174280^2 .

It is a cyclic number.

It is not a de Polignac number, because 401000000081 - 2² = 401000000077 is a prime.

It is a super-2 number, since 2×401000000081² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (401000000381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200500000040 + 200500000041.

It is an arithmetic number, because the mean of its divisors is an integer number (200500000041).

Almost surely, 2^401000000081 is an apocalyptic number.

It is an amenable number.

401000000081 is a deficient number, since it is larger than the sum of its proper divisors (1).

401000000081 is an equidigital number, since it uses as much as digits as its factorization.

401000000081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 401000000081 its reverse (180000000104), we get a palindrome (581000000185).

The spelling of 401000000081 in words is "four hundred one billion, eighty-one", and thus it is an aban number.