66215441 has 2 divisors, whose sum is σ = 66215442. Its totient is φ = 66215440.

The previous prime is 66215431. The next prime is 66215447. The reversal of 66215441 is 14451266.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60902416 + 5313025 = 7804^2 + 2305^2 .

It is a cyclic number.

It is not a de Polignac number, because 66215441 - 2²² = 62021137 is a prime.

It is a super-3 number, since 3×66215441³ (a number of 24 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (66215447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33107720 + 33107721.

It is an arithmetic number, because the mean of its divisors is an integer number (33107721).

Almost surely, 2^66215441 is an apocalyptic number.

It is an amenable number.

66215441 is a deficient number, since it is larger than the sum of its proper divisors (1).

66215441 is an equidigital number, since it uses as much as digits as its factorization.

66215441 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 29.

The square root of 66215441 is about 8137.2870786276. The cubic root of 66215441 is about 404.5632460849.

The spelling of 66215441 in words is "sixty-six million, two hundred fifteen thousand, four hundred forty-one".