1979975381 has 2 divisors, whose sum is σ = 1979975382. Its totient is φ = 1979975380.

The previous prime is 1979975369. The next prime is 1979975383. The reversal of 1979975381 is 1835799791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1975002481 + 4972900 = 44441^2 + 2230^2 .

It is a cyclic number.

It is not a de Polignac number, because 1979975381 - 2¹⁰ = 1979974357 is a prime.

It is a super-2 number, since 2×1979975381² = 7840605018732190322, which contains 22 as substring.

Together with 1979975383, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1979975381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1979975383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 989987690 + 989987691.

It is an arithmetic number, because the mean of its divisors is an integer number (989987691).

Almost surely, 2^1979975381 is an apocalyptic number.

It is an amenable number.

1979975381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1979975381 is an equidigital number, since it uses as much as digits as its factorization.

1979975381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4286520, while the sum is 59.

The square root of 1979975381 is about 44496.9142862738. The cubic root of 1979975381 is about 1255.7020312020.

The spelling of 1979975381 in words is "one billion, nine hundred seventy-nine million, nine hundred seventy-five thousand, three hundred eighty-one".