66540765 has 8 divisors (see below), whose sum is σ = 106465248. Its totient is φ = 35488400.

The previous prime is 66540757. The next prime is 66540769. The reversal of 66540765 is 56704566.

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

It is not a de Polignac number, because 66540765 - 2³ = 66540757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66540769) 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, 2218011 + ... + 2218040.

It is an arithmetic number, because the mean of its divisors is an integer number (13308156).

Almost surely, 2^66540765 is an apocalyptic number.

It is an amenable number.

66540765 is a deficient number, since it is larger than the sum of its proper divisors (39924483).

66540765 is a wasteful number, since it uses less digits than its factorization.

66540765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4436059.

The product of its (nonzero) digits is 151200, while the sum is 39.

The square root of 66540765 is about 8157.2522947375. The cubic root of 66540765 is about 405.2247190627.

The spelling of 66540765 in words is "sixty-six million, five hundred forty thousand, seven hundred sixty-five".