66221383 has 4 divisors (see below), whose sum is σ = 66323448. Its totient is φ = 66119320.

The previous prime is 66221381. The next prime is 66221399. The reversal of 66221383 is 38312266.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 38312266 = 2 ⋅19156133.

It is a cyclic number.

It is not a de Polignac number, because 66221383 - 2¹ = 66221381 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 (66221381) 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, 50053 + ... + 51358.

It is an arithmetic number, because the mean of its divisors is an integer number (16580862).

Almost surely, 2^66221383 is an apocalyptic number.

66221383 is a deficient number, since it is larger than the sum of its proper divisors (102065).

66221383 is a wasteful number, since it uses less digits than its factorization.

66221383 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102064.

The product of its digits is 10368, while the sum is 31.

The square root of 66221383 is about 8137.6521798366. The cubic root of 66221383 is about 404.5753472045.

The spelling of 66221383 in words is "sixty-six million, two hundred twenty-one thousand, three hundred eighty-three".