66663253 has 4 divisors (see below), whose sum is σ = 68289228. Its totient is φ = 65037280.

The previous prime is 66663217. The next prime is 66663271. The reversal of 66663253 is 35236666.

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 4915089 + 61748164 = 2217^2 + 7858^2 .

It is a cyclic number.

It is not a de Polignac number, because 66663253 - 2¹⁷ = 66532181 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66663283) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 812926 + ... + 813007.

It is an arithmetic number, because the mean of its divisors is an integer number (17072307).

Almost surely, 2^66663253 is an apocalyptic number.

It is an amenable number.

66663253 is a deficient number, since it is larger than the sum of its proper divisors (1625975).

66663253 is a wasteful number, since it uses less digits than its factorization.

66663253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1625974.

The product of its digits is 116640, while the sum is 37.

The square root of 66663253 is about 8164.7567630640. The cubic root of 66663253 is about 405.4732120500.

The spelling of 66663253 in words is "sixty-six million, six hundred sixty-three thousand, two hundred fifty-three".