66299540 has 12 divisors (see below), whose sum is σ = 139229076. Its totient is φ = 26519808.

The previous prime is 66299537. The next prime is 66299543. The reversal of 66299540 is 4599266.

It is an interprime number because it is at equal distance from previous prime (66299537) and next prime (66299543).

It can be written as a sum of positive squares in 2 ways, for example, as 39715204 + 26584336 = 6302^2 + 5156^2 .

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66299543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1657469 + ... + 1657508.

It is an arithmetic number, because the mean of its divisors is an integer number (11602423).

Almost surely, 2^66299540 is an apocalyptic number.

It is an amenable number.

66299540 is an abundant number, since it is smaller than the sum of its proper divisors (72929536).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66299540 is a wasteful number, since it uses less digits than its factorization.

66299540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3314986 (or 3314984 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 66299540 is about 8142.4529473617. The cubic root of 66299540 is about 404.7344497091.

The spelling of 66299540 in words is "sixty-six million, two hundred ninety-nine thousand, five hundred forty".