66525905 has 4 divisors (see below), whose sum is σ = 79831092. Its totient is φ = 53220720.

The previous prime is 66525871. The next prime is 66525923. The reversal of 66525905 is 50952566.

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 48344209 + 18181696 = 6953^2 + 4264^2 .

It is not a de Polignac number, because 66525905 - 2⁸ = 66525649 is a prime.

It is a Duffinian number.

It is a Curzon 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, 6652586 + ... + 6652595.

It is an arithmetic number, because the mean of its divisors is an integer number (19957773).

Almost surely, 2^66525905 is an apocalyptic number.

It is an amenable number.

66525905 is a deficient number, since it is larger than the sum of its proper divisors (13305187).

66525905 is a wasteful number, since it uses less digits than its factorization.

66525905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13305186.

The product of its (nonzero) digits is 81000, while the sum is 38.

The square root of 66525905 is about 8156.3413979553. The cubic root of 66525905 is about 405.1945516526.

The spelling of 66525905 in words is "sixty-six million, five hundred twenty-five thousand, nine hundred five".