66415121 has 8 divisors (see below), whose sum is σ = 68699904. Its totient is φ = 64162080.

The previous prime is 66415079. The next prime is 66415147. The reversal of 66415121 is 12151466.

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 66415121 - 2⁶ = 66415057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66415171) 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, 3641 + ... + 12086.

It is an arithmetic number, because the mean of its divisors is an integer number (8587488).

Almost surely, 2^66415121 is an apocalyptic number.

It is an amenable number.

66415121 is a deficient number, since it is larger than the sum of its proper divisors (2284783).

66415121 is a wasteful number, since it uses less digits than its factorization.

66415121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15871.

The product of its digits is 1440, while the sum is 26.

The square root of 66415121 is about 8149.5472880400. The cubic root of 66415121 is about 404.9695064172.

Adding to 66415121 its reverse (12151466), we get a palindrome (78566587).

The spelling of 66415121 in words is "sixty-six million, four hundred fifteen thousand, one hundred twenty-one".