66455566 has 4 divisors (see below), whose sum is σ = 99683352. Its totient is φ = 33227782.

The previous prime is 66455539. The next prime is 66455581. The reversal of 66455566 is 66555466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66555466 = 2 ⋅33277733.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16613890 + ... + 16613893.

It is an arithmetic number, because the mean of its divisors is an integer number (24920838).

Almost surely, 2^66455566 is an apocalyptic number.

66455566 is a deficient number, since it is larger than the sum of its proper divisors (33227786).

66455566 is a wasteful number, since it uses less digits than its factorization.

66455566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33227785.

The product of its digits is 648000, while the sum is 43.

The square root of 66455566 is about 8152.0283365553. The cubic root of 66455566 is about 405.0516948696.

The spelling of 66455566 in words is "sixty-six million, four hundred fifty-five thousand, five hundred sixty-six".