387389659666 has 4 divisors (see below), whose sum is σ = 581084489502. Its totient is φ = 193694829832.

The previous prime is 387389659649. The next prime is 387389659717. The reversal of 387389659666 is 666956983783.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 666956983783 = 418871 ⋅1592273.

It can be written as a sum of positive squares in only one way, i.e., 283418881641 + 103970778025 = 532371^2 + 322445^2 .

It is a super-2 number, since 2×387389659666² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 387389659592 and 387389659601.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 96847414915 + ... + 96847414918.

Almost surely, 2^387389659666 is an apocalyptic number.

387389659666 is a deficient number, since it is larger than the sum of its proper divisors (193694829836).

387389659666 is a wasteful number, since it uses less digits than its factorization.

387389659666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193694829835.

The product of its digits is 2116316160, while the sum is 76.

The spelling of 387389659666 in words is "three hundred eighty-seven billion, three hundred eighty-nine million, six hundred fifty-nine thousand, six hundred sixty-six".