1797639157 has 2 divisors, whose sum is σ = 1797639158. Its totient is φ = 1797639156.

The previous prime is 1797639139. The next prime is 1797639161. The reversal of 1797639157 is 7519367971.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1527168241 + 270470916 = 39079^2 + 16446^2 .

It is a cyclic number.

It is not a de Polignac number, because 1797639157 - 2⁷ = 1797639029 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1797639098 and 1797639107.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1797630157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 898819578 + 898819579.

It is an arithmetic number, because the mean of its divisors is an integer number (898819579).

Almost surely, 2^1797639157 is an apocalyptic number.

It is an amenable number.

1797639157 is a deficient number, since it is larger than the sum of its proper divisors (1).

1797639157 is an equidigital number, since it uses as much as digits as its factorization.

1797639157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2500470, while the sum is 55.

The square root of 1797639157 is about 42398.5749406746. The cubic root of 1797639157 is about 1215.9083470297.

The spelling of 1797639157 in words is "one billion, seven hundred ninety-seven million, six hundred thirty-nine thousand, one hundred fifty-seven".