66542147 has 12 divisors (see below), whose sum is σ = 78721560. Its totient is φ = 56066976.

The previous prime is 66542143. The next prime is 66542191. The reversal of 66542147 is 74124566.

It is not a de Polignac number, because 66542147 - 2² = 66542143 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66542143) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8618 + ... + 14399.

It is an arithmetic number, because the mean of its divisors is an integer number (6560130).

Almost surely, 2^66542147 is an apocalyptic number.

66542147 is a deficient number, since it is larger than the sum of its proper divisors (12179413).

66542147 is a wasteful number, since it uses less digits than its factorization.

66542147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23090 (or 23083 counting only the distinct ones).

The product of its digits is 40320, while the sum is 35.

The square root of 66542147 is about 8157.3370041944. The cubic root of 66542147 is about 405.2275244442.

The spelling of 66542147 in words is "sixty-six million, five hundred forty-two thousand, one hundred forty-seven".