386721881 has 16 divisors (see below), whose sum is σ = 487579008. Its totient is φ = 298512000.

The previous prime is 386721857. The next prime is 386721887. The reversal of 386721881 is 188127683.

It is a cyclic number.

It is not a de Polignac number, because 386721881 - 2¹⁰ = 386720857 is a prime.

It is a super-2 number, since 2×386721881² = 299107626488356322, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (386721887) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48095 + ... + 55556.

It is an arithmetic number, because the mean of its divisors is an integer number (30473688).

Almost surely, 2^386721881 is an apocalyptic number.

It is an amenable number.

386721881 is a deficient number, since it is larger than the sum of its proper divisors (100857127).

386721881 is a wasteful number, since it uses less digits than its factorization.

386721881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103712.

The product of its digits is 129024, while the sum is 44.

The square root of 386721881 is about 19665.2455107990. The cubic root of 386721881 is about 728.5615516191.

The spelling of 386721881 in words is "three hundred eighty-six million, seven hundred twenty-one thousand, eight hundred eighty-one".