139940864 has 66 divisors (see below), whose sum is σ = 325534410. Its totient is φ = 59953152.

The previous prime is 139940819. The next prime is 139940903. The reversal of 139940864 is 468049931.

It can be written as a sum of positive squares in only one way, i.e., 125440000 + 14500864 = 11200^2 + 3808^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 48782 + ... + 51570.

Almost surely, 2^139940864 is an apocalyptic number.

139940864 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 139940864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162767205).

139940864 is an abundant number, since it is smaller than the sum of its proper divisors (185593546).

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

139940864 is an equidigital number, since it uses as much as digits as its factorization.

139940864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2823 (or 2798 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 44.

The square root of 139940864 is about 11829.6603501538. The cubic root of 139940864 is about 519.1762895718.

The spelling of 139940864 in words is "one hundred thirty-nine million, nine hundred forty thousand, eight hundred sixty-four".