391090138384 has 135 divisors (see below), whose sum is σ = 850412078607. Its totient is φ = 174103564800.

The previous prime is 391090138379. The next prime is 391090138423. The reversal of 391090138384 is 483831090193.

The square root of 391090138384 is 625372.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 248302890000 + 142787248384 = 498300^2 + 377872^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1678498332 + ... + 1678498564.

Almost surely, 2^391090138384 is an apocalyptic number.

391090138384 is the 625372-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 391090138384

391090138384 is an abundant number, since it is smaller than the sum of its proper divisors (459321940223).

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

391090138384 is an equidigital number, since it uses as much as digits as its factorization.

391090138384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618 (or 307 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 49.

Multiplying 391090138384 by its sum of digits (49), we get a square (19163416780816 = 4377604²).

The spelling of 391090138384 in words is "three hundred ninety-one billion, ninety million, one hundred thirty-eight thousand, three hundred eighty-four".