136447991 has 2 divisors, whose sum is σ = 136447992. Its totient is φ = 136447990.

The previous prime is 136447981. The next prime is 136447999. The reversal of 136447991 is 199744631.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 136447991 - 2¹⁰ = 136446967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (136447999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68223995 + 68223996.

It is an arithmetic number, because the mean of its divisors is an integer number (68223996).

Almost surely, 2^136447991 is an apocalyptic number.

136447991 is a deficient number, since it is larger than the sum of its proper divisors (1).

136447991 is an equidigital number, since it uses as much as digits as its factorization.

136447991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 44.

The square root of 136447991 is about 11681.0954537663. The cubic root of 136447991 is about 514.8203615153.

The spelling of 136447991 in words is "one hundred thirty-six million, four hundred forty-seven thousand, nine hundred ninety-one".