66265261 has 8 divisors (see below), whose sum is σ = 70404120. Its totient is φ = 62250048.

The previous prime is 66265237. The next prime is 66265271. The reversal of 66265261 is 16256266.

It can be written as a sum of positive squares in 4 ways, for example, as 11594025 + 54671236 = 3405^2 + 7394^2 .

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 66265261 - 2¹⁹ = 65740973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66265271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29806 + ... + 31951.

It is an arithmetic number, because the mean of its divisors is an integer number (8800515).

Almost surely, 2^66265261 is an apocalyptic number.

It is an amenable number.

66265261 is a deficient number, since it is larger than the sum of its proper divisors (4138859).

66265261 is a wasteful number, since it uses less digits than its factorization.

66265261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61823.

The product of its digits is 25920, while the sum is 34.

The square root of 66265261 is about 8140.3477198459. The cubic root of 66265261 is about 404.6646840970.

The spelling of 66265261 in words is "sixty-six million, two hundred sixty-five thousand, two hundred sixty-one".