139973321 has 2 divisors, whose sum is σ = 139973322. Its totient is φ = 139973320.

The previous prime is 139973263. The next prime is 139973329. The reversal of 139973321 is 123379931.

139973321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 108388921 + 31584400 = 10411^2 + 5620^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139973321 is a prime.

It is equal to p_7910795 and since 139973321 and 7910795 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (139973329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69986660 + 69986661.

It is an arithmetic number, because the mean of its divisors is an integer number (69986661).

Almost surely, 2^139973321 is an apocalyptic number.

It is an amenable number.

139973321 is a deficient number, since it is larger than the sum of its proper divisors (1).

139973321 is an equidigital number, since it uses as much as digits as its factorization.

139973321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30618, while the sum is 38.

The square root of 139973321 is about 11831.0321189658. The cubic root of 139973321 is about 519.2164246254.

The spelling of 139973321 in words is "one hundred thirty-nine million, nine hundred seventy-three thousand, three hundred twenty-one".