1901992789 has 2 divisors, whose sum is σ = 1901992790. Its totient is φ = 1901992788.

The previous prime is 1901992699. The next prime is 1901992819. The reversal of 1901992789 is 9872991091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1444760100 + 457232689 = 38010^2 + 21383^2 .

It is a cyclic number.

It is not a de Polignac number, because 1901992789 - 2⁷ = 1901992661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1901992189) 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, 950996394 + 950996395.

It is an arithmetic number, because the mean of its divisors is an integer number (950996395).

Almost surely, 2^1901992789 is an apocalyptic number.

It is an amenable number.

1901992789 is a deficient number, since it is larger than the sum of its proper divisors (1).

1901992789 is an equidigital number, since it uses as much as digits as its factorization.

1901992789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 734832, while the sum is 55.

The square root of 1901992789 is about 43611.8423022922. The cubic root of 1901992789 is about 1238.9951947141.

The spelling of 1901992789 in words is "one billion, nine hundred one million, nine hundred ninety-two thousand, seven hundred eighty-nine".