139023691 has 2 divisors, whose sum is σ = 139023692. Its totient is φ = 139023690.

The previous prime is 139023649. The next prime is 139023721. The reversal of 139023691 is 196320931.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 139023691 - 2⁹ = 139023179 is a prime.

It is equal to p_7860076 and since 139023691 and 7860076 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 (139023631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69511845 + 69511846.

It is an arithmetic number, because the mean of its divisors is an integer number (69511846).

Almost surely, 2^139023691 is an apocalyptic number.

139023691 is a deficient number, since it is larger than the sum of its proper divisors (1).

139023691 is an equidigital number, since it uses as much as digits as its factorization.

139023691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 139023691 is about 11790.8308019410. The cubic root of 139023691 is about 518.0395747506.

The spelling of 139023691 in words is "one hundred thirty-nine million, twenty-three thousand, six hundred ninety-one".