66525861 has 16 divisors (see below), whose sum is σ = 90256320. Its totient is φ = 43580160.

The previous prime is 66525853. The next prime is 66525869. The reversal of 66525861 is 16852566.

It is an interprime number because it is at equal distance from previous prime (66525853) and next prime (66525869).

It is not a de Polignac number, because 66525861 - 2³ = 66525853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66525869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42061 + ... + 43613.

It is an arithmetic number, because the mean of its divisors is an integer number (5641020).

Almost surely, 2^66525861 is an apocalyptic number.

It is an amenable number.

66525861 is a deficient number, since it is larger than the sum of its proper divisors (23730459).

66525861 is a wasteful number, since it uses less digits than its factorization.

66525861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1796.

The product of its digits is 86400, while the sum is 39.

The square root of 66525861 is about 8156.3387006671. The cubic root of 66525861 is about 405.1944623212.

The spelling of 66525861 in words is "sixty-six million, five hundred twenty-five thousand, eight hundred sixty-one".