66772729 has 4 divisors (see below), whose sum is σ = 68926720. Its totient is φ = 64618740.

The previous prime is 66772709. The next prime is 66772733. The reversal of 66772729 is 92727766.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66772729 - 2⁵ = 66772697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66772709) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1076949 + ... + 1077010.

It is an arithmetic number, because the mean of its divisors is an integer number (17231680).

Almost surely, 2^66772729 is an apocalyptic number.

It is an amenable number.

66772729 is a deficient number, since it is larger than the sum of its proper divisors (2153991).

66772729 is a wasteful number, since it uses less digits than its factorization.

66772729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2153990.

The product of its digits is 444528, while the sum is 46.

The square root of 66772729 is about 8171.4581930033. The cubic root of 66772729 is about 405.6950499507.

The spelling of 66772729 in words is "sixty-six million, seven hundred seventy-two thousand, seven hundred twenty-nine".