66533149 has 4 divisors (see below), whose sum is σ = 67444636. Its totient is φ = 65621664.

The previous prime is 66533143. The next prime is 66533171. The reversal of 66533149 is 94133566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94133566 = 2 ⋅47066783.

It can be written as a sum of positive squares in 2 ways, for example, as 13505625 + 53027524 = 3675^2 + 7282^2 .

It is a cyclic number.

It is not a de Polignac number, because 66533149 - 2⁷ = 66533021 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 (66533143) 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, 455634 + ... + 455779.

It is an arithmetic number, because the mean of its divisors is an integer number (16861159).

Almost surely, 2^66533149 is an apocalyptic number.

It is an amenable number.

66533149 is a deficient number, since it is larger than the sum of its proper divisors (911487).

66533149 is an equidigital number, since it uses as much as digits as its factorization.

66533149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 911486.

The product of its digits is 58320, while the sum is 37.

The square root of 66533149 is about 8156.7854575194. The cubic root of 66533149 is about 405.2092583186.

The spelling of 66533149 in words is "sixty-six million, five hundred thirty-three thousand, one hundred forty-nine".