1938197869 has 2 divisors, whose sum is σ = 1938197870. Its totient is φ = 1938197868.

The previous prime is 1938197839. The next prime is 1938197887. The reversal of 1938197869 is 9687918391.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1675919844 + 262278025 = 40938^2 + 16195^2 .

It is a cyclic number.

It is not a de Polignac number, because 1938197869 - 2¹⁹ = 1937673581 is a prime.

It is a super-2 number, since 2×1938197869² = 7513221958792282322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1938197839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 969098934 + 969098935.

It is an arithmetic number, because the mean of its divisors is an integer number (969098935).

Almost surely, 2^1938197869 is an apocalyptic number.

It is an amenable number.

1938197869 is a deficient number, since it is larger than the sum of its proper divisors (1).

1938197869 is an equidigital number, since it uses as much as digits as its factorization.

1938197869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5878656, while the sum is 61.

The square root of 1938197869 is about 44024.9686995914. The cubic root of 1938197869 is about 1246.8073981636.

The spelling of 1938197869 in words is "one billion, nine hundred thirty-eight million, one hundred ninety-seven thousand, eight hundred sixty-nine".