66747121 has 8 divisors (see below), whose sum is σ = 76331840. Its totient is φ = 57174768.

The previous prime is 66747103. The next prime is 66747181. The reversal of 66747121 is 12174766.

It is a happy number.

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

It is not a de Polignac number, because 66747121 - 2⁵ = 66747089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66747181) 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, 19915 + ... + 23023.

It is an arithmetic number, because the mean of its divisors is an integer number (9541480).

Almost surely, 2^66747121 is an apocalyptic number.

It is an amenable number.

66747121 is a deficient number, since it is larger than the sum of its proper divisors (9584719).

66747121 is a wasteful number, since it uses less digits than its factorization.

66747121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6183.

The product of its digits is 14112, while the sum is 34.

The square root of 66747121 is about 8169.8911253456. The cubic root of 66747121 is about 405.6431806353.

The spelling of 66747121 in words is "sixty-six million, seven hundred forty-seven thousand, one hundred twenty-one".