66415273 has 2 divisors, whose sum is σ = 66415274. Its totient is φ = 66415272.

The previous prime is 66415253. The next prime is 66415301. The reversal of 66415273 is 37251466.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55995289 + 10419984 = 7483^2 + 3228^2 .

It is a cyclic number.

It is not a de Polignac number, because 66415273 - 2¹⁷ = 66284201 is a prime.

It is not a weakly prime, because it can be changed into another prime (66415253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33207636 + 33207637.

It is an arithmetic number, because the mean of its divisors is an integer number (33207637).

Almost surely, 2^66415273 is an apocalyptic number.

It is an amenable number.

66415273 is a deficient number, since it is larger than the sum of its proper divisors (1).

66415273 is an equidigital number, since it uses as much as digits as its factorization.

66415273 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 34.

The square root of 66415273 is about 8149.5566137060. The cubic root of 66415273 is about 404.9698153595.

It can be divided in two parts, 664152 and 73, that added together give a square (664225 = 815²).

The spelling of 66415273 in words is "sixty-six million, four hundred fifteen thousand, two hundred seventy-three".