64841581 has 4 divisors (see below), whose sum is σ = 74104672. Its totient is φ = 55578492.

The previous prime is 64841527. The next prime is 64841599. The reversal of 64841581 is 18514846.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64841581 - 2¹⁵ = 64808813 is a prime.

It is a super-2 number, since 2×64841581² = 8408861253159122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64841581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64841521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4631535 + ... + 4631548.

It is an arithmetic number, because the mean of its divisors is an integer number (18526168).

Almost surely, 2^64841581 is an apocalyptic number.

It is an amenable number.

64841581 is a deficient number, since it is larger than the sum of its proper divisors (9263091).

64841581 is an equidigital number, since it uses as much as digits as its factorization.

64841581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9263090.

The product of its digits is 30720, while the sum is 37.

The square root of 64841581 is about 8052.4270254377. The cubic root of 64841581 is about 401.7456643077.

The spelling of 64841581 in words is "sixty-four million, eight hundred forty-one thousand, five hundred eighty-one".