64000091 has 2 divisors, whose sum is σ = 64000092. Its totient is φ = 64000090.

The previous prime is 64000067. The next prime is 64000109. The reversal of 64000091 is 19000046.

Together with next prime (64000109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64000091 is a prime.

It is a Chen prime.

64000091 is a modest number, since divided by 91 gives 64 as remainder.

It is not a weakly prime, because it can be changed into another prime (64000031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32000045 + 32000046.

It is an arithmetic number, because the mean of its divisors is an integer number (32000046).

Almost surely, 2^64000091 is an apocalyptic number.

64000091 is a deficient number, since it is larger than the sum of its proper divisors (1).

64000091 is an equidigital number, since it uses as much as digits as its factorization.

64000091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 64000091 is about 8000.0056874980. The cubic root of 64000091 is about 400.0001895832. Note that the first 3 decimals are identical.

The spelling of 64000091 in words is "sixty-four million, ninety-one", and thus it is an aban number.