139666320 has 120 divisors (see below), whose sum is σ = 485292600. Its totient is φ = 35954688.

The previous prime is 139666313. The next prime is 139666333. The reversal of 139666320 is 23666931.

It can be written as a sum of positive squares in 4 ways, for example, as 34152336 + 105513984 = 5844^2 + 10272^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17536 + ... + 24224.

It is an arithmetic number, because the mean of its divisors is an integer number (4044105).

Almost surely, 2^139666320 is an apocalyptic number.

139666320 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 139666320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242646300).

139666320 is an abundant number, since it is smaller than the sum of its proper divisors (345626280).

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

139666320 is a wasteful number, since it uses less digits than its factorization.

139666320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6737 (or 6728 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 36.

The square root of 139666320 is about 11818.0506006701. The cubic root of 139666320 is about 518.8365507108.

The spelling of 139666320 in words is "one hundred thirty-nine million, six hundred sixty-six thousand, three hundred twenty".