1660813393 has 2 divisors, whose sum is σ = 1660813394. Its totient is φ = 1660813392.

The previous prime is 1660813391. The next prime is 1660813421. The reversal of 1660813393 is 3933180661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1593047569 + 67765824 = 39913^2 + 8232^2 .

It is a cyclic number.

It is not a de Polignac number, because 1660813393 - 2¹ = 1660813391 is a prime.

It is a super-2 number, since 2×1660813393² = 5516602252736344898, which contains 22 as substring.

Together with 1660813391, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1660813391) 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, 830406696 + 830406697.

It is an arithmetic number, because the mean of its divisors is an integer number (830406697).

Almost surely, 2^1660813393 is an apocalyptic number.

It is an amenable number.

1660813393 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660813393 is an equidigital number, since it uses as much as digits as its factorization.

1660813393 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69984, while the sum is 40.

The square root of 1660813393 is about 40753.0783254468. The cubic root of 1660813393 is about 1184.2415088307.

The spelling of 1660813393 in words is "one billion, six hundred sixty million, eight hundred thirteen thousand, three hundred ninety-three".