139638436 has 36 divisors (see below), whose sum is σ = 285039216. Its totient is φ = 59682000.

The previous prime is 139638413. The next prime is 139638449. The reversal of 139638436 is 634836931.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 139638392 and 139638401.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 95511 + ... + 96961.

It is an arithmetic number, because the mean of its divisors is an integer number (7917756).

Almost surely, 2^139638436 is an apocalyptic number.

It is an amenable number.

139638436 is an abundant number, since it is smaller than the sum of its proper divisors (145400780).

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

139638436 is a wasteful number, since it uses less digits than its factorization.

139638436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1960 (or 1951 counting only the distinct ones).

The product of its digits is 279936, while the sum is 43.

The square root of 139638436 is about 11816.8708209915. The cubic root of 139638436 is about 518.8020203118.

The spelling of 139638436 in words is "one hundred thirty-nine million, six hundred thirty-eight thousand, four hundred thirty-six".