66763121 has 8 divisors (see below), whose sum is σ = 67737384. Its totient is φ = 65795200.

The previous prime is 66763091. The next prime is 66763153. The reversal of 66763121 is 12136766.

It can be written as a sum of positive squares in 4 ways, for example, as 3385600 + 63377521 = 1840^2 + 7961^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66763121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66763421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22115 + ... + 24951.

It is an arithmetic number, because the mean of its divisors is an integer number (8467173).

Almost surely, 2^66763121 is an apocalyptic number.

It is an amenable number.

66763121 is a deficient number, since it is larger than the sum of its proper divisors (974263).

66763121 is a wasteful number, since it uses less digits than its factorization.

66763121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3171.

The product of its digits is 9072, while the sum is 32.

The square root of 66763121 is about 8170.8702718866. The cubic root of 66763121 is about 405.6755903845.

Adding to 66763121 its reverse (12136766), we get a palindrome (78899887).

The spelling of 66763121 in words is "sixty-six million, seven hundred sixty-three thousand, one hundred twenty-one".