139421440 has 36 divisors (see below), whose sum is σ = 333960984. Its totient is φ = 55768064.

The previous prime is 139421419. The next prime is 139421441. The reversal of 139421440 is 44124931.

It is a junction number, because it is equal to n+sod(n) for n = 139421399 and 139421408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139421441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53182 + ... + 55741.

It is an arithmetic number, because the mean of its divisors is an integer number (9276694).

Almost surely, 2^139421440 is an apocalyptic number.

139421440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

139421440 is an abundant number, since it is smaller than the sum of its proper divisors (194539544).

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

139421440 is an equidigital number, since it uses as much as digits as its factorization.

139421440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108944 (or 108930 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 139421440 is about 11807.6856326716. The cubic root of 139421440 is about 518.5331441780.

The spelling of 139421440 in words is "one hundred thirty-nine million, four hundred twenty-one thousand, four hundred forty".