1660643357 has 2 divisors, whose sum is σ = 1660643358. Its totient is φ = 1660643356.

The previous prime is 1660643261. The next prime is 1660643363. The reversal of 1660643357 is 7533460661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1479094681 + 181548676 = 38459^2 + 13474^2 .

It is a cyclic number.

It is not a de Polignac number, because 1660643357 - 2³⁰ = 586901533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1660633357) 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, 830321678 + 830321679.

It is an arithmetic number, because the mean of its divisors is an integer number (830321679).

Almost surely, 2^1660643357 is an apocalyptic number.

It is an amenable number.

1660643357 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660643357 is an equidigital number, since it uses as much as digits as its factorization.

1660643357 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 272160, while the sum is 41.

The square root of 1660643357 is about 40750.9920983526. The cubic root of 1660643357 is about 1184.2010927787.

The spelling of 1660643357 in words is "one billion, six hundred sixty million, six hundred forty-three thousand, three hundred fifty-seven".