1660570981 has 2 divisors, whose sum is σ = 1660570982. Its totient is φ = 1660570980.

The previous prime is 1660570979. The next prime is 1660571027. The reversal of 1660570981 is 1890750661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1618774756 + 41796225 = 40234^2 + 6465^2 .

It is a cyclic number.

It is not a de Polignac number, because 1660570981 - 2¹ = 1660570979 is a prime.

It is a super-2 number, since 2×1660570981² = 5514991965878604722, which contains 22 as substring.

Together with 1660570979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1660570781) 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, 830285490 + 830285491.

It is an arithmetic number, because the mean of its divisors is an integer number (830285491).

Almost surely, 2^1660570981 is an apocalyptic number.

It is an amenable number.

1660570981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660570981 is an equidigital number, since it uses as much as digits as its factorization.

1660570981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 43.

The square root of 1660570981 is about 40750.1040612168. The cubic root of 1660570981 is about 1184.1838888071.

The spelling of 1660570981 in words is "one billion, six hundred sixty million, five hundred seventy thousand, nine hundred eighty-one".