139391784 has 96 divisors (see below), whose sum is σ = 433667520. Its totient is φ = 39621888.

The previous prime is 139391783. The next prime is 139391797. The reversal of 139391784 is 487193931.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139391783) 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 23 ways as a sum of consecutive naturals, for example, 116839 + ... + 118025.

It is an arithmetic number, because the mean of its divisors is an integer number (4517370).

Almost surely, 2^139391784 is an apocalyptic number.

139391784 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 139391784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (216833760).

139391784 is an abundant number, since it is smaller than the sum of its proper divisors (294275736).

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

139391784 is a wasteful number, since it uses less digits than its factorization.

139391784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1439 (or 1432 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 139391784 is about 11806.4297736445. The cubic root of 139391784 is about 518.4963762573.

The spelling of 139391784 in words is "one hundred thirty-nine million, three hundred ninety-one thousand, seven hundred eighty-four".