66375461 has 4 divisors (see below), whose sum is σ = 68664300. Its totient is φ = 64086624.

The previous prime is 66375457. The next prime is 66375467. The reversal of 66375461 is 16457366.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 50495236 + 15880225 = 7106^2 + 3985^2 .

It is a cyclic number.

It is not a de Polignac number, because 66375461 - 2² = 66375457 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66375467) 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, 1144376 + ... + 1144433.

It is an arithmetic number, because the mean of its divisors is an integer number (17166075).

Almost surely, 2^66375461 is an apocalyptic number.

66375461 is the 3644-th centered decagonal number.

It is an amenable number.

66375461 is a deficient number, since it is larger than the sum of its proper divisors (2288839).

66375461 is a wasteful number, since it uses less digits than its factorization.

66375461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2288838.

The product of its digits is 90720, while the sum is 38.

The square root of 66375461 is about 8147.1136606776. The cubic root of 66375461 is about 404.8888807584. Note that the first 5 decimals are identical.

The spelling of 66375461 in words is "sixty-six million, three hundred seventy-five thousand, four hundred sixty-one".