66427021 has 8 divisors (see below), whose sum is σ = 70282080. Its totient is φ = 62607888.

The previous prime is 66426953. The next prime is 66427037. The reversal of 66427021 is 12072466.

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

It is a de Polignac number, because none of the positive numbers 2^k-66427021 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 (66427061) 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, 5131 + ... + 12616.

It is an arithmetic number, because the mean of its divisors is an integer number (8785260).

Almost surely, 2^66427021 is an apocalyptic number.

It is an amenable number.

66427021 is a deficient number, since it is larger than the sum of its proper divisors (3855059).

66427021 is a wasteful number, since it uses less digits than its factorization.

66427021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17963.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 66427021 is about 8150.2773572437. The cubic root of 66427021 is about 404.9936919202.

Adding to 66427021 its reverse (12072466), we get a palindrome (78499487).

The spelling of 66427021 in words is "sixty-six million, four hundred twenty-seven thousand, twenty-one".