136866251 has 2 divisors, whose sum is σ = 136866252. Its totient is φ = 136866250.

The previous prime is 136866239. The next prime is 136866259. The reversal of 136866251 is 152668631.

It is a strong prime.

It is an emirp because it is prime and its reverse (152668631) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 136866251 - 2⁶ = 136866187 is a prime.

It is equal to p_7745069 and since 136866251 and 7745069 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 (136866259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68433125 + 68433126.

It is an arithmetic number, because the mean of its divisors is an integer number (68433126).

Almost surely, 2^136866251 is an apocalyptic number.

136866251 is a deficient number, since it is larger than the sum of its proper divisors (1).

136866251 is an equidigital number, since it uses as much as digits as its factorization.

136866251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 38.

The square root of 136866251 is about 11698.9850414470. The cubic root of 136866251 is about 515.3458587343.

The spelling of 136866251 in words is "one hundred thirty-six million, eight hundred sixty-six thousand, two hundred fifty-one".