381666688 has 64 divisors (see below), whose sum is σ = 822442320. Its totient is φ = 175380480.

The previous prime is 381666683. The next prime is 381666697. The reversal of 381666688 is 886666183.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (52).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381666683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 577078 + ... + 577738.

Almost surely, 2^381666688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 381666688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (411221160).

381666688 is an abundant number, since it is smaller than the sum of its proper divisors (440775632).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

381666688 is a wasteful number, since it uses less digits than its factorization.

381666688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1035 (or 1023 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 52.

The square root of 381666688 is about 19536.2915621159. The cubic root of 381666688 is about 725.3730544616.

The spelling of 381666688 in words is "three hundred eighty-one million, six hundred sixty-six thousand, six hundred eighty-eight".