66724355 has 4 divisors (see below), whose sum is σ = 80069232. Its totient is φ = 53379480.

The previous prime is 66724351. The next prime is 66724363. The reversal of 66724355 is 55342766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55342766 = 2 ⋅27671383.

It is not a de Polignac number, because 66724355 - 2² = 66724351 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66724351) 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, 6672431 + ... + 6672440.

It is an arithmetic number, because the mean of its divisors is an integer number (20017308).

Almost surely, 2^66724355 is an apocalyptic number.

66724355 is a deficient number, since it is larger than the sum of its proper divisors (13344877).

66724355 is a wasteful number, since it uses less digits than its factorization.

66724355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13344876.

The product of its digits is 151200, while the sum is 38.

The square root of 66724355 is about 8168.4977198993. The cubic root of 66724355 is about 405.5970566844.

The spelling of 66724355 in words is "sixty-six million, seven hundred twenty-four thousand, three hundred fifty-five".