66481087 has 4 divisors (see below), whose sum is σ = 66552976. Its totient is φ = 66409200.

The previous prime is 66481073. The next prime is 66481097. The reversal of 66481087 is 78018466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78018466 = 2 ⋅39009233.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66481087 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66481097) 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, 34539 + ... + 36412.

It is an arithmetic number, because the mean of its divisors is an integer number (16638244).

Almost surely, 2^66481087 is an apocalyptic number.

66481087 is a deficient number, since it is larger than the sum of its proper divisors (71889).

66481087 is an equidigital number, since it uses as much as digits as its factorization.

66481087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71888.

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 66481087 is about 8153.5935022541. The cubic root of 66481087 is about 405.1035390412.

The spelling of 66481087 in words is "sixty-six million, four hundred eighty-one thousand, eighty-seven".