66725905 has 4 divisors (see below), whose sum is σ = 80071092. Its totient is φ = 53380720.

The previous prime is 66725899. The next prime is 66725951. The reversal of 66725905 is 50952766.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14409616 + 52316289 = 3796^2 + 7233^2 .

It is not a de Polignac number, because 66725905 - 2¹¹ = 66723857 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6672586 + ... + 6672595.

It is an arithmetic number, because the mean of its divisors is an integer number (20017773).

Almost surely, 2^66725905 is an apocalyptic number.

It is an amenable number.

66725905 is a deficient number, since it is larger than the sum of its proper divisors (13345187).

66725905 is a wasteful number, since it uses less digits than its factorization.

66725905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13345186.

The product of its (nonzero) digits is 113400, while the sum is 40.

The square root of 66725905 is about 8168.5925960351. The cubic root of 66725905 is about 405.6001973196.

The spelling of 66725905 in words is "sixty-six million, seven hundred twenty-five thousand, nine hundred five".