66666465 has 12 divisors (see below), whose sum is σ = 115555284. Its totient is φ = 35555424.

The previous prime is 66666437. The next prime is 66666487. The reversal of 66666465 is 56466666.

It can be written as a sum of positive squares in 2 ways, for example, as 18766224 + 47900241 = 4332^2 + 6921^2 .

It is not a de Polignac number, because 66666465 - 2⁵ = 66666433 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 1481477 = 66666465 / (6 + 6 + 6 + 6 + 6 + 4 + 6 + 5).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 66666465.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 740694 + ... + 740783.

It is an arithmetic number, because the mean of its divisors is an integer number (9629607).

Almost surely, 2^66666465 is an apocalyptic number.

It is an amenable number.

66666465 is a deficient number, since it is larger than the sum of its proper divisors (48888819).

66666465 is a wasteful number, since it uses less digits than its factorization.

66666465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1481488 (or 1481485 counting only the distinct ones).

The product of its digits is 933120, while the sum is 45.

The square root of 66666465 is about 8164.9534597571. The cubic root of 66666465 is about 405.4797241787.

It can be divided in two parts, 6666 and 6465, that added together give a palindrome (13131).

The spelling of 66666465 in words is "sixty-six million, six hundred sixty-six thousand, four hundred sixty-five".