66459840 has 112 divisors (see below), whose sum is σ = 213311232. Its totient is φ = 17529856.

The previous prime is 66459839. The next prime is 66459859. The reversal of 66459840 is 4895466.

It is a junction number, because it is equal to n+sod(n) for n = 66459792 and 66459801.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 102397 + ... + 103043.

Almost surely, 2^66459840 is an apocalyptic number.

66459840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66459840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106655616).

66459840 is an abundant number, since it is smaller than the sum of its proper divisors (146851392).

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

66459840 is a wasteful number, since it uses less digits than its factorization.

66459840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 774 (or 764 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 42.

The square root of 66459840 is about 8152.2904756884. The cubic root of 66459840 is about 405.0603781344.

The spelling of 66459840 in words is "sixty-six million, four hundred fifty-nine thousand, eight hundred forty".