66515449 has 16 divisors (see below), whose sum is σ = 89308800. Its totient is φ = 47842560.

The previous prime is 66515431. The next prime is 66515467. The reversal of 66515449 is 94451566.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66515431) and next prime (66515467).

It is a cyclic number.

It is not a de Polignac number, because 66515449 - 2¹³ = 66507257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66510449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32224 + ... + 34225.

It is an arithmetic number, because the mean of its divisors is an integer number (5581800).

Almost surely, 2^66515449 is an apocalyptic number.

It is an amenable number.

66515449 is a deficient number, since it is larger than the sum of its proper divisors (22793351).

66515449 is a wasteful number, since it uses less digits than its factorization.

66515449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66480.

The product of its digits is 129600, while the sum is 40.

The square root of 66515449 is about 8155.7003991074. The cubic root of 66515449 is about 405.1733221470.

It can be divided in two parts, 6651 and 5449, that added together give a square (12100 = 110²).

The spelling of 66515449 in words is "sixty-six million, five hundred fifteen thousand, four hundred forty-nine".