66440153 has 6 divisors (see below), whose sum is σ = 71944254. Its totient is φ = 61329216.

The previous prime is 66440137. The next prime is 66440173. The reversal of 66440153 is 35104466.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 375769 + 66064384 = 613^2 + 8128^2 .

It is not a de Polignac number, because 66440153 - 2⁴ = 66440137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66440113) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 196400 + ... + 196737.

It is an arithmetic number, because the mean of its divisors is an integer number (11990709).

Almost surely, 2^66440153 is an apocalyptic number.

It is an amenable number.

66440153 is a deficient number, since it is larger than the sum of its proper divisors (5504101).

66440153 is a wasteful number, since it uses less digits than its factorization.

66440153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393163 (or 393150 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 66440153 is about 8151.0829341873. The cubic root of 66440153 is about 405.0203779819.

The spelling of 66440153 in words is "sixty-six million, four hundred forty thousand, one hundred fifty-three".