2181081037 has 2 divisors, whose sum is σ = 2181081038. Its totient is φ = 2181081036.

The previous prime is 2181081029. The next prime is 2181081061. The reversal of 2181081037 is 7301801812.

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., 2091324361 + 89756676 = 45731^2 + 9474^2 .

It is a cyclic number.

It is not a de Polignac number, because 2181081037 - 2³ = 2181081029 is a prime.

It is a super-4 number, since 4×2181081037⁴ (a number of 38 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2181081017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1090540518 + 1090540519.

It is an arithmetic number, because the mean of its divisors is an integer number (1090540519).

Almost surely, 2^2181081037 is an apocalyptic number.

It is an amenable number.

2181081037 is a deficient number, since it is larger than the sum of its proper divisors (1).

2181081037 is an equidigital number, since it uses as much as digits as its factorization.

2181081037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 31.

The square root of 2181081037 is about 46702.0453192363. The cubic root of 2181081037 is about 1296.8525509034.

Adding to 2181081037 its reverse (7301801812), we get a palindrome (9482882849).

The spelling of 2181081037 in words is "two billion, one hundred eighty-one million, eighty-one thousand, thirty-seven".