1666956977 has 8 divisors (see below), whose sum is σ = 1928047296. Its totient is φ = 1411605072.

The previous prime is 1666956961. The next prime is 1666956979. The reversal of 1666956977 is 7796596661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1666956977 - 2⁴ = 1666956961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1666956979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1433978 + ... + 1435139.

It is an arithmetic number, because the mean of its divisors is an integer number (241005912).

Almost surely, 2^1666956977 is an apocalyptic number.

It is an amenable number.

1666956977 is a deficient number, since it is larger than the sum of its proper divisors (261090319).

1666956977 is an equidigital number, since it uses as much as digits as its factorization.

1666956977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2869207.

The product of its digits is 25719120, while the sum is 62.

The square root of 1666956977 is about 40828.3844524860. The cubic root of 1666956977 is about 1185.6999376921.

The spelling of 1666956977 in words is "one billion, six hundred sixty-six million, nine hundred fifty-six thousand, nine hundred seventy-seven".