66172765 has 8 divisors (see below), whose sum is σ = 79784928. Its totient is φ = 52686480.

The previous prime is 66172753. The next prime is 66172907. The reversal of 66172765 is 56727166.

It is a happy number.

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

It is not a de Polignac number, because 66172765 - 2⁷ = 66172637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30307 + ... + 32416.

It is an arithmetic number, because the mean of its divisors is an integer number (9973116).

Almost surely, 2^66172765 is an apocalyptic number.

It is an amenable number.

66172765 is a deficient number, since it is larger than the sum of its proper divisors (13612163).

66172765 is a wasteful number, since it uses less digits than its factorization.

66172765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62939.

The product of its digits is 105840, while the sum is 40.

The square root of 66172765 is about 8134.6644061080. The cubic root of 66172765 is about 404.4763134334.

The spelling of 66172765 in words is "sixty-six million, one hundred seventy-two thousand, seven hundred sixty-five".