381751785 has 48 divisors (see below), whose sum is σ = 688746240. Its totient is φ = 203128560.

The previous prime is 381751759. The next prime is 381751789. The reversal of 381751785 is 587157183.

It is not a de Polignac number, because 381751785 - 2²¹ = 379654633 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a nialpdrome in base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 381751785.

It is not an unprimeable number, because it can be changed into a prime (381751789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 885520 + ... + 885950.

It is an arithmetic number, because the mean of its divisors is an integer number (14348880).

Almost surely, 2^381751785 is an apocalyptic number.

It is an amenable number.

381751785 is a deficient number, since it is larger than the sum of its proper divisors (306994455).

381751785 is an frugal number, since it uses more digits than its factorization.

381751785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469 (or 439 counting only the distinct ones).

The product of its digits is 235200, while the sum is 45.

The square root of 381751785 is about 19538.4693617489. The cubic root of 381751785 is about 725.4269605580.

The spelling of 381751785 in words is "three hundred eighty-one million, seven hundred fifty-one thousand, seven hundred eighty-five".