66251489 has 2 divisors, whose sum is σ = 66251490. Its totient is φ = 66251488.

The previous prime is 66251483. The next prime is 66251501. The reversal of 66251489 is 98415266.

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., 59413264 + 6838225 = 7708^2 + 2615^2 .

It is a cyclic number.

It is not a de Polignac number, because 66251489 - 2⁴ = 66251473 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66251483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33125744 + 33125745.

It is an arithmetic number, because the mean of its divisors is an integer number (33125745).

Almost surely, 2^66251489 is an apocalyptic number.

It is an amenable number.

66251489 is a deficient number, since it is larger than the sum of its proper divisors (1).

66251489 is an equidigital number, since it uses as much as digits as its factorization.

66251489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 41.

The square root of 66251489 is about 8139.5017660788. The cubic root of 66251489 is about 404.6366481494.

The spelling of 66251489 in words is "sixty-six million, two hundred fifty-one thousand, four hundred eighty-nine".