91256129 has 2 divisors, whose sum is σ = 91256130. Its totient is φ = 91256128.

The previous prime is 91256117. The next prime is 91256131. The reversal of 91256129 is 92165219.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50908225 + 40347904 = 7135^2 + 6352^2 .

It is a cyclic number.

It is not a de Polignac number, because 91256129 - 2¹² = 91252033 is a prime.

Together with 91256131, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (91256159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45628064 + 45628065.

It is an arithmetic number, because the mean of its divisors is an integer number (45628065).

Almost surely, 2^91256129 is an apocalyptic number.

It is an amenable number.

91256129 is a deficient number, since it is larger than the sum of its proper divisors (1).

91256129 is an equidigital number, since it uses as much as digits as its factorization.

91256129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9720, while the sum is 35.

The square root of 91256129 is about 9552.8073884068. The cubic root of 91256129 is about 450.2157467522.

The spelling of 91256129 in words is "ninety-one million, two hundred fifty-six thousand, one hundred twenty-nine".