66515441 has 4 divisors (see below), whose sum is σ = 70428132. Its totient is φ = 62602752.

The previous prime is 66515431. The next prime is 66515467. The reversal of 66515441 is 14451566.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14451566 = 2 ⋅7225783.

It can be written as a sum of positive squares in 2 ways, for example, as 44622400 + 21893041 = 6680^2 + 4679^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66515441 is a prime.

It is a super-3 number, since 3×66515441³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 66515398 and 66515407.

It is not an unprimeable number, because it can be changed into a prime (66515401) 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, 1956320 + ... + 1956353.

It is an arithmetic number, because the mean of its divisors is an integer number (17607033).

Almost surely, 2^66515441 is an apocalyptic number.

It is an amenable number.

66515441 is a deficient number, since it is larger than the sum of its proper divisors (3912691).

66515441 is a wasteful number, since it uses less digits than its factorization.

66515441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3912690.

The product of its digits is 14400, while the sum is 32.

The square root of 66515441 is about 8155.6999086528. The cubic root of 66515441 is about 405.1733059033.

The spelling of 66515441 in words is "sixty-six million, five hundred fifteen thousand, four hundred forty-one".