64542091 has 2 divisors, whose sum is σ = 64542092. Its totient is φ = 64542090.

The previous prime is 64542083. The next prime is 64542109. The reversal of 64542091 is 19024546.

Together with next prime (64542109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64542091 - 2³ = 64542083 is a prime.

It is not a weakly prime, because it can be changed into another prime (64546091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32271045 + 32271046.

It is an arithmetic number, because the mean of its divisors is an integer number (32271046).

Almost surely, 2^64542091 is an apocalyptic number.

64542091 is a deficient number, since it is larger than the sum of its proper divisors (1).

64542091 is an equidigital number, since it uses as much as digits as its factorization.

64542091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 64542091 is about 8033.8092459306. The cubic root of 64542091 is about 401.1261825565.

The spelling of 64542091 in words is "sixty-four million, five hundred forty-two thousand, ninety-one".