66541819 has 8 divisors (see below), whose sum is σ = 70400000. Its totient is φ = 62719272.

The previous prime is 66541753. The next prime is 66541823. The reversal of 66541819 is 91814566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66541819 - 2¹¹ = 66539771 is a prime.

It is a super-2 number, since 2×66541819² = 8855627351657522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66541879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5019 + ... + 12580.

It is an arithmetic number, because the mean of its divisors is an integer number (8800000).

Almost surely, 2^66541819 is an apocalyptic number.

66541819 is a deficient number, since it is larger than the sum of its proper divisors (3858181).

66541819 is a wasteful number, since it uses less digits than its factorization.

66541819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17817.

The product of its digits is 51840, while the sum is 40.

The square root of 66541819 is about 8157.3168995694. The cubic root of 66541819 is about 405.2268586263.

The spelling of 66541819 in words is "sixty-six million, five hundred forty-one thousand, eight hundred nineteen".