139007221 has 2 divisors, whose sum is σ = 139007222. Its totient is φ = 139007220.

The previous prime is 139007213. The next prime is 139007233. The reversal of 139007221 is 122700931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76755121 + 62252100 = 8761^2 + 7890^2 .

It is a cyclic number.

It is not a de Polignac number, because 139007221 - 2³ = 139007213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139007291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69503610 + 69503611.

It is an arithmetic number, because the mean of its divisors is an integer number (69503611).

Almost surely, 2^139007221 is an apocalyptic number.

It is an amenable number.

139007221 is a deficient number, since it is larger than the sum of its proper divisors (1).

139007221 is an equidigital number, since it uses as much as digits as its factorization.

139007221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 139007221 is about 11790.1323571875. The cubic root of 139007221 is about 518.0191167296.

The spelling of 139007221 in words is "one hundred thirty-nine million, seven thousand, two hundred twenty-one".