66450840 has 32 divisors (see below), whose sum is σ = 199352880. Its totient is φ = 17720192.

The previous prime is 66450821. The next prime is 66450859. The reversal of 66450840 is 4805466.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66450821) and next prime (66450859).

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 276759 + ... + 276998.

Almost surely, 2^66450840 is an apocalyptic number.

66450840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66450840 is an abundant number, since it is smaller than the sum of its proper divisors (132902040).

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

66450840 is a wasteful number, since it uses less digits than its factorization.

66450840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 553771 (or 553767 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 33.

The square root of 66450840 is about 8151.7384648920. The cubic root of 66450840 is about 405.0420928663.

The spelling of 66450840 in words is "sixty-six million, four hundred fifty thousand, eight hundred forty".