66649359 has 40 divisors (see below), whose sum is σ = 109351040. Its totient is φ = 36006768.

The previous prime is 66649357. The next prime is 66649361. The reversal of 66649359 is 95394666.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66649357) and next prime (66649361).

It is not a de Polignac number, because 66649359 - 2¹ = 66649357 is a prime.

It is a super-2 number, since 2×66649359² = 8884274110221762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66649351) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 136614 + ... + 137100.

It is an arithmetic number, because the mean of its divisors is an integer number (2733776).

Almost surely, 2^66649359 is an apocalyptic number.

66649359 is a deficient number, since it is larger than the sum of its proper divisors (42701681).

66649359 is an equidigital number, since it uses as much as digits as its factorization.

66649359 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 537 (or 516 counting only the distinct ones).

The product of its digits is 1049760, while the sum is 48.

The square root of 66649359 is about 8163.9058666793. The cubic root of 66649359 is about 405.4450404263.

The spelling of 66649359 in words is "sixty-six million, six hundred forty-nine thousand, three hundred fifty-nine".