139678649 has 6 divisors (see below), whose sum is σ = 153531210. Its totient is φ = 126980480.

The previous prime is 139678639. The next prime is 139678673. The reversal of 139678649 is 946876931.

139678649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 90117049 + 49561600 = 9493^2 + 7040^2 .

It is not a de Polignac number, because 139678649 - 2¹⁶ = 139613113 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 139678649.

It is not an unprimeable number, because it can be changed into a prime (139678639) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 577064 + ... + 577305.

It is an arithmetic number, because the mean of its divisors is an integer number (25588535).

Almost surely, 2^139678649 is an apocalyptic number.

It is an amenable number.

139678649 is a deficient number, since it is larger than the sum of its proper divisors (13852561).

139678649 is a wasteful number, since it uses less digits than its factorization.

139678649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1154391 (or 1154380 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 53.

The square root of 139678649 is about 11818.5722064892. The cubic root of 139678649 is about 518.8518169722.

The spelling of 139678649 in words is "one hundred thirty-nine million, six hundred seventy-eight thousand, six hundred forty-nine".