139521680 has 80 divisors (see below), whose sum is σ = 341121024. Its totient is φ = 52968960.

The previous prime is 139521677. The next prime is 139521743. The reversal of 139521680 is 86125931.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 139521680.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 351242 + ... + 351638.

Almost surely, 2^139521680 is an apocalyptic number.

139521680 is a gapful number since it is divisible by the number (10) 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 139521680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170560512).

139521680 is an abundant number, since it is smaller than the sum of its proper divisors (201599344).

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

139521680 is a wasteful number, since it uses less digits than its factorization.

139521680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624 (or 618 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 139521680 is about 11811.9295629461. The cubic root of 139521680 is about 518.6573845400.

The spelling of 139521680 in words is "one hundred thirty-nine million, five hundred twenty-one thousand, six hundred eighty".