1666877101 has 4 divisors (see below), whose sum is σ = 1666960992. Its totient is φ = 1666793212.

The previous prime is 1666877077. The next prime is 1666877129. The reversal of 1666877101 is 1017786661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1666877101 - 2²³ = 1658488493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666877141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6546 + ... + 58108.

It is an arithmetic number, because the mean of its divisors is an integer number (416740248).

Almost surely, 2^1666877101 is an apocalyptic number.

It is an amenable number.

1666877101 is a deficient number, since it is larger than the sum of its proper divisors (83891).

1666877101 is an equidigital number, since it uses as much as digits as its factorization.

1666877101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83890.

The product of its (nonzero) digits is 84672, while the sum is 43.

The square root of 1666877101 is about 40827.4062487442. The cubic root of 1666877101 is about 1185.6809988948.

The spelling of 1666877101 in words is "one billion, six hundred sixty-six million, eight hundred seventy-seven thousand, one hundred one".