381806564 has 12 divisors (see below), whose sum is σ = 679115388. Its totient is φ = 187773600.

The previous prime is 381806549. The next prime is 381806599. The reversal of 381806564 is 465608183.

It can be written as a sum of positive squares in 2 ways, for example, as 162766564 + 219040000 = 12758^2 + 14800^2 .

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 782147 + ... + 782634.

It is an arithmetic number, because the mean of its divisors is an integer number (56592949).

Almost surely, 2^381806564 is an apocalyptic number.

It is an amenable number.

381806564 is a deficient number, since it is larger than the sum of its proper divisors (297308824).

381806564 is a wasteful number, since it uses less digits than its factorization.

381806564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1564846 (or 1564844 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 41.

The square root of 381806564 is about 19539.8711357061. The cubic root of 381806564 is about 725.4616569798.

It can be divided in two parts, 38180 and 6564, that added together give a palindrome (44744).

The spelling of 381806564 in words is "three hundred eighty-one million, eight hundred six thousand, five hundred sixty-four".