863261884638 has 64 divisors (see below), whose sum is σ = 1984228646400. Its totient is φ = 278009910720.

The previous prime is 863261884633. The next prime is 863261884643. The reversal of 863261884638 is 836488162368.

863261884638 is a `hidden beast` number, since 8 + 6 + 3 + 2 + 618 + 8 + 4 + 6 + 3 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (863261884633) and next prime (863261884643).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (863261884633) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1664728 + ... + 2120811.

It is an arithmetic number, because the mean of its divisors is an integer number (31003572600).

Almost surely, 2^863261884638 is an apocalyptic number.

863261884638 is an abundant number, since it is smaller than the sum of its proper divisors (1120966761762).

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

863261884638 is a wasteful number, since it uses less digits than its factorization.

863261884638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3785694 (or 3785688 counting only the distinct ones).

The product of its digits is 63700992, while the sum is 63.

The spelling of 863261884638 in words is "eight hundred sixty-three billion, two hundred sixty-one million, eight hundred eighty-four thousand, six hundred thirty-eight".