66018421 has 8 divisors (see below), whose sum is σ = 75720384. Its totient is φ = 56384160.

The previous prime is 66018377. The next prime is 66018451. The reversal of 66018421 is 12481066.

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

It is not a de Polignac number, because 66018421 - 2¹³ = 66010229 is a prime.

It is a super-2 number, since 2×66018421² = 8716863822666482, 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 66018421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66018451) 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, 14815 + ... + 18748.

It is an arithmetic number, because the mean of its divisors is an integer number (9465048).

Almost surely, 2^66018421 is an apocalyptic number.

It is an amenable number.

66018421 is a deficient number, since it is larger than the sum of its proper divisors (9701963).

66018421 is a wasteful number, since it uses less digits than its factorization.

66018421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33851.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 66018421 is about 8125.1720597166. The cubic root of 66018421 is about 404.1615963842.

Adding to 66018421 its reverse (12481066), we get a palindrome (78499487).

The spelling of 66018421 in words is "sixty-six million, eighteen thousand, four hundred twenty-one".