66673553 has 2 divisors, whose sum is σ = 66673554. Its totient is φ = 66673552.

The previous prime is 66673547. The next prime is 66673559. The reversal of 66673553 is 35537666.

It is a balanced prime because it is at equal distance from previous prime (66673547) and next prime (66673559).

It can be written as a sum of positive squares in only one way, i.e., 39037504 + 27636049 = 6248^2 + 5257^2 .

It is a cyclic number.

It is not a de Polignac number, because 66673553 - 2¹⁸ = 66411409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66673553.

It is not a weakly prime, because it can be changed into another prime (66673559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33336776 + 33336777.

It is an arithmetic number, because the mean of its divisors is an integer number (33336777).

Almost surely, 2^66673553 is an apocalyptic number.

It is an amenable number.

66673553 is a deficient number, since it is larger than the sum of its proper divisors (1).

66673553 is an equidigital number, since it uses as much as digits as its factorization.

66673553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 340200, while the sum is 41.

The square root of 66673553 is about 8165.3874984596. The cubic root of 66673553 is about 405.4940939143.

The spelling of 66673553 in words is "sixty-six million, six hundred seventy-three thousand, five hundred fifty-three".