66523493 has 2 divisors, whose sum is σ = 66523494. Its totient is φ = 66523492.

The previous prime is 66523487. The next prime is 66523507. The reversal of 66523493 is 39432566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60481729 + 6041764 = 7777^2 + 2458^2 .

It is a cyclic number.

It is not a de Polignac number, because 66523493 - 2¹⁴ = 66507109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66523403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33261746 + 33261747.

It is an arithmetic number, because the mean of its divisors is an integer number (33261747).

Almost surely, 2^66523493 is an apocalyptic number.

It is an amenable number.

66523493 is a deficient number, since it is larger than the sum of its proper divisors (1).

66523493 is an equidigital number, since it uses as much as digits as its factorization.

66523493 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 38.

The square root of 66523493 is about 8156.1935362030. The cubic root of 66523493 is about 405.1896546075.

The spelling of 66523493 in words is "sixty-six million, five hundred twenty-three thousand, four hundred ninety-three".