66249705 has 16 divisors (see below), whose sum is σ = 106104960. Its totient is φ = 35298048.

The previous prime is 66249691. The next prime is 66249719. The reversal of 66249705 is 50794266.

It is an interprime number because it is at equal distance from previous prime (66249691) and next prime (66249719).

It is not a de Polignac number, because 66249705 - 2⁶ = 66249641 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21969 + ... + 24801.

It is an arithmetic number, because the mean of its divisors is an integer number (6631560).

Almost surely, 2^66249705 is an apocalyptic number.

It is an amenable number.

66249705 is a deficient number, since it is larger than the sum of its proper divisors (39855255).

66249705 is a wasteful number, since it uses less digits than its factorization.

66249705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4400.

The product of its (nonzero) digits is 90720, while the sum is 39.

The square root of 66249705 is about 8139.3921763237. The cubic root of 66249705 is about 404.6330161392.

The spelling of 66249705 in words is "sixty-six million, two hundred forty-nine thousand, seven hundred five".