1993785137 has 2 divisors, whose sum is σ = 1993785138. Its totient is φ = 1993785136.

The previous prime is 1993785133. The next prime is 1993785139. The reversal of 1993785137 is 7315873991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1313410081 + 680375056 = 36241^2 + 26084^2 .

It is a cyclic number.

It is not a de Polignac number, because 1993785137 - 2² = 1993785133 is a prime.

Together with 1993785139, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1993785133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 996892568 + 996892569.

It is an arithmetic number, because the mean of its divisors is an integer number (996892569).

Almost surely, 2^1993785137 is an apocalyptic number.

It is an amenable number.

1993785137 is a deficient number, since it is larger than the sum of its proper divisors (1).

1993785137 is an equidigital number, since it uses as much as digits as its factorization.

1993785137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1428840, while the sum is 53.

The square root of 1993785137 is about 44651.8212058590. The cubic root of 1993785137 is about 1258.6146563302.

The spelling of 1993785137 in words is "one billion, nine hundred ninety-three million, seven hundred eighty-five thousand, one hundred thirty-seven".