3786866721 has 80 divisors (see below), whose sum is σ = 6463328256. Its totient is φ = 2188620000.

The previous prime is 3786866669. The next prime is 3786866747. The reversal of 3786866721 is 1276686873.

It is not a de Polignac number, because 3786866721 - 2⁷ = 3786866593 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3786866761) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1960126 + ... + 1962056.

Almost surely, 2^3786866721 is an apocalyptic number.

3786866721 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

3786866721 is a deficient number, since it is larger than the sum of its proper divisors (2676461535).

3786866721 is a wasteful number, since it uses less digits than its factorization.

3786866721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2056 (or 2047 counting only the distinct ones).

The product of its digits is 4064256, while the sum is 54.

The square root of 3786866721 is about 61537.5228701968. The cubic root of 3786866721 is about 1558.6909247247.

The spelling of 3786866721 in words is "three billion, seven hundred eighty-six million, eight hundred sixty-six thousand, seven hundred twenty-one".