66394440 has 96 divisors (see below), whose sum is σ = 246617280. Its totient is φ = 15175296.

The previous prime is 66394429. The next prime is 66394483. The reversal of 66394440 is 4449366.

66394440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 66394395 and 66394404.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10654 + ... + 15693.

It is an arithmetic number, because the mean of its divisors is an integer number (2568930).

Almost surely, 2^66394440 is an apocalyptic number.

66394440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66394440 is an abundant number, since it is smaller than the sum of its proper divisors (180222840).

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

66394440 is a wasteful number, since it uses less digits than its factorization.

66394440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26371 (or 26364 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The square root of 66394440 is about 8148.2783457611. The cubic root of 66394440 is about 404.9274675778.

The spelling of 66394440 in words is "sixty-six million, three hundred ninety-four thousand, four hundred forty".