66720603 has 4 divisors (see below), whose sum is σ = 88960808. Its totient is φ = 44480400.

The previous prime is 66720559. The next prime is 66720659. The reversal of 66720603 is 30602766.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 66720603 - 2¹⁰ = 66719579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66720103) 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, 11120098 + ... + 11120103.

It is an arithmetic number, because the mean of its divisors is an integer number (22240202).

Almost surely, 2^66720603 is an apocalyptic number.

66720603 is a deficient number, since it is larger than the sum of its proper divisors (22240205).

66720603 is a wasteful number, since it uses less digits than its factorization.

66720603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22240204.

The product of its (nonzero) digits is 9072, while the sum is 30.

The square root of 66720603 is about 8168.2680538778. The cubic root of 66720603 is about 405.5894541197.

The spelling of 66720603 in words is "sixty-six million, seven hundred twenty thousand, six hundred three".