66421331 has 8 divisors (see below), whose sum is σ = 67443600. Its totient is φ = 65404512.

The previous prime is 66421307. The next prime is 66421343. The reversal of 66421331 is 13312466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66421331 - 2¹⁸ = 66159187 is a prime.

It is a super-2 number, since 2×66421331² = 8823586423623122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66421331.

It is not an unprimeable number, because it can be changed into a prime (66421231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27821 + ... + 30113.

It is an arithmetic number, because the mean of its divisors is an integer number (8430450).

Almost surely, 2^66421331 is an apocalyptic number.

66421331 is a deficient number, since it is larger than the sum of its proper divisors (1022269).

66421331 is a wasteful number, since it uses less digits than its factorization.

66421331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2725.

The product of its digits is 2592, while the sum is 26.

The square root of 66421331 is about 8149.9282818930. The cubic root of 66421331 is about 404.9821279519.

Adding to 66421331 its reverse (13312466), we get a palindrome (79733797).

The spelling of 66421331 in words is "sixty-six million, four hundred twenty-one thousand, three hundred thirty-one".