1938276181 has 2 divisors, whose sum is σ = 1938276182. Its totient is φ = 1938276180.

The previous prime is 1938276169. The next prime is 1938276227. The reversal of 1938276181 is 1816728391.

It is a happy number.

It is an a-pointer prime, because the next prime (1938276227) can be obtained adding 1938276181 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1933009156 + 5267025 = 43966^2 + 2295^2 .

It is an emirp because it is prime and its reverse (1816728391) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1938276181 is a prime.

It is a super-2 number, since 2×1938276181² = 7513829107663889522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1938276101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 969138090 + 969138091.

It is an arithmetic number, because the mean of its divisors is an integer number (969138091).

Almost surely, 2^1938276181 is an apocalyptic number.

It is an amenable number.

1938276181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1938276181 is an equidigital number, since it uses as much as digits as its factorization.

1938276181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 46.

The square root of 1938276181 is about 44025.8580949878. The cubic root of 1938276181 is about 1246.8241901654.

The spelling of 1938276181 in words is "one billion, nine hundred thirty-eight million, two hundred seventy-six thousand, one hundred eighty-one".