139987428 has 96 divisors (see below), whose sum is σ = 389270784. Its totient is φ = 38320128.

The previous prime is 139987423. The next prime is 139987457. The reversal of 139987428 is 824789931.

It is not an unprimeable number, because it can be changed into a prime (139987423) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 226576 + ... + 227192.

It is an arithmetic number, because the mean of its divisors is an integer number (4054904).

Almost surely, 2^139987428 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 139987428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194635392).

139987428 is an abundant number, since it is smaller than the sum of its proper divisors (249283356).

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

139987428 is a wasteful number, since it uses less digits than its factorization.

139987428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741 (or 739 counting only the distinct ones).

The product of its digits is 870912, while the sum is 51.

The square root of 139987428 is about 11831.6282903073. The cubic root of 139987428 is about 519.2338668542.

The spelling of 139987428 in words is "one hundred thirty-nine million, nine hundred eighty-seven thousand, four hundred twenty-eight".