64487581 has 2 divisors, whose sum is σ = 64487582. Its totient is φ = 64487580.

The previous prime is 64487537. The next prime is 64487587. The reversal of 64487581 is 18578446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59151481 + 5336100 = 7691^2 + 2310^2 .

It is a cyclic number.

It is not a de Polignac number, because 64487581 - 2¹⁹ = 63963293 is a prime.

It is a super-2 number, since 2×64487581² = 8317296206463122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64487587) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32243790 + 32243791.

It is an arithmetic number, because the mean of its divisors is an integer number (32243791).

Almost surely, 2^64487581 is an apocalyptic number.

It is an amenable number.

64487581 is a deficient number, since it is larger than the sum of its proper divisors (1).

64487581 is an equidigital number, since it uses as much as digits as its factorization.

64487581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 215040, while the sum is 43.

The square root of 64487581 is about 8030.4159917155. The cubic root of 64487581 is about 401.0132250206.

The spelling of 64487581 in words is "sixty-four million, four hundred eighty-seven thousand, five hundred eighty-one".