1993639693 has 2 divisors, whose sum is σ = 1993639694. Its totient is φ = 1993639692.

The previous prime is 1993639639. The next prime is 1993639751. The reversal of 1993639693 is 3969363991.

Together with previous prime (1993639639) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (1993639751) can be obtained adding 1993639693 to its sum of digits (58).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1309137124 + 684502569 = 36182^2 + 26163^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1993639693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1993639603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 996819846 + 996819847.

It is an arithmetic number, because the mean of its divisors is an integer number (996819847).

Almost surely, 2^1993639693 is an apocalyptic number.

It is an amenable number.

1993639693 is a deficient number, since it is larger than the sum of its proper divisors (1).

1993639693 is an equidigital number, since it uses as much as digits as its factorization.

1993639693 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6377292, while the sum is 58.

The square root of 1993639693 is about 44650.1925303800. The cubic root of 1993639693 is about 1258.5840508254.

The spelling of 1993639693 in words is "one billion, nine hundred ninety-three million, six hundred thirty-nine thousand, six hundred ninety-three".