66523145 has 16 divisors (see below), whose sum is σ = 86828112. Its totient is φ = 48633600.

The previous prime is 66523141. The next prime is 66523169. The reversal of 66523145 is 54132566.

It can be written as a sum of positive squares in 8 ways, for example, as 2347024 + 64176121 = 1532^2 + 8011^2 .

It is not a de Polignac number, because 66523145 - 2² = 66523141 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66523141) 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, 1499 + ... + 11631.

It is an arithmetic number, because the mean of its divisors is an integer number (5426757).

Almost surely, 2^66523145 is an apocalyptic number.

66523145 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66523145 is a deficient number, since it is larger than the sum of its proper divisors (20304967).

66523145 is a wasteful number, since it uses less digits than its factorization.

66523145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10252.

The product of its digits is 21600, while the sum is 32.

The square root of 66523145 is about 8156.1722026941. The cubic root of 66523145 is about 405.1889480589.

The spelling of 66523145 in words is "sixty-six million, five hundred twenty-three thousand, one hundred forty-five".