660539897 has 2 divisors, whose sum is σ = 660539898. Its totient is φ = 660539896.

The previous prime is 660539861. The next prime is 660539923. The reversal of 660539897 is 798935066.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 575088361 + 85451536 = 23981^2 + 9244^2 .

It is a cyclic number.

It is not a de Polignac number, because 660539897 - 2¹⁰ = 660538873 is a prime.

It is not a weakly prime, because it can be changed into another prime (660539857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330269948 + 330269949.

It is an arithmetic number, because the mean of its divisors is an integer number (330269949).

Almost surely, 2^660539897 is an apocalyptic number.

It is an amenable number.

660539897 is a deficient number, since it is larger than the sum of its proper divisors (1).

660539897 is an equidigital number, since it uses as much as digits as its factorization.

660539897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2449440, while the sum is 53.

The square root of 660539897 is about 25700.9707404215. The cubic root of 660539897 is about 870.8961115115.

The spelling of 660539897 in words is "six hundred sixty million, five hundred thirty-nine thousand, eight hundred ninety-seven".