1866668387 has 4 divisors (see below), whose sum is σ = 1880917896. Its totient is φ = 1852418880.

The previous prime is 1866668333. The next prime is 1866668407. The reversal of 1866668387 is 7838666681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7838666681 = 1187 ⋅6603763.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1866668387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1866668887) 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, 7124558 + ... + 7124819.

It is an arithmetic number, because the mean of its divisors is an integer number (470229474).

Almost surely, 2^1866668387 is an apocalyptic number.

1866668387 is a deficient number, since it is larger than the sum of its proper divisors (14249509).

1866668387 is a wasteful number, since it uses less digits than its factorization.

1866668387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14249508.

The product of its digits is 13934592, while the sum is 59.

The square root of 1866668387 is about 43204.9578983709. The cubic root of 1866668387 is about 1231.2768785495.

The spelling of 1866668387 in words is "one billion, eight hundred sixty-six million, six hundred sixty-eight thousand, three hundred eighty-seven".