66253917 has 4 divisors (see below), whose sum is σ = 88338560. Its totient is φ = 44169276.

The previous prime is 66253897. The next prime is 66253919. The reversal of 66253917 is 71935266.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66253917 - 2¹⁵ = 66221149 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 (66253919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11042317 + ... + 11042322.

It is an arithmetic number, because the mean of its divisors is an integer number (22084640).

Almost surely, 2^66253917 is an apocalyptic number.

It is an amenable number.

66253917 is a deficient number, since it is larger than the sum of its proper divisors (22084643).

66253917 is a wasteful number, since it uses less digits than its factorization.

66253917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22084642.

The product of its digits is 68040, while the sum is 39.

The square root of 66253917 is about 8139.6509138906. The cubic root of 66253917 is about 404.6415911617.

The spelling of 66253917 in words is "sixty-six million, two hundred fifty-three thousand, nine hundred seventeen".