66942541 has 2 divisors, whose sum is σ = 66942542. Its totient is φ = 66942540.

The previous prime is 66942511. The next prime is 66942607. The reversal of 66942541 is 14524966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66357316 + 585225 = 8146^2 + 765^2 .

It is a cyclic number.

It is not a de Polignac number, because 66942541 - 2²⁵ = 33388109 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66942541.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66942511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33471270 + 33471271.

It is an arithmetic number, because the mean of its divisors is an integer number (33471271).

Almost surely, 2^66942541 is an apocalyptic number.

It is an amenable number.

66942541 is a deficient number, since it is larger than the sum of its proper divisors (1).

66942541 is an equidigital number, since it uses as much as digits as its factorization.

66942541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 37.

The square root of 66942541 is about 8181.8421519851. The cubic root of 66942541 is about 406.0386711205.

The spelling of 66942541 in words is "sixty-six million, nine hundred forty-two thousand, five hundred forty-one".