66435440 has 40 divisors (see below), whose sum is σ = 157757760. Its totient is φ = 26007296.

The previous prime is 66435389. The next prime is 66435451. The reversal of 66435440 is 4453466.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 66435397 and 66435406.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5075 + ... + 12594.

It is an arithmetic number, because the mean of its divisors is an integer number (3943944).

Almost surely, 2^66435440 is an apocalyptic number.

It is an amenable number.

66435440 is an abundant number, since it is smaller than the sum of its proper divisors (91322320).

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

66435440 is a wasteful number, since it uses less digits than its factorization.

66435440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17729 (or 17723 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 32.

The square root of 66435440 is about 8150.7938263705. The cubic root of 66435440 is about 405.0108009110.

The spelling of 66435440 in words is "sixty-six million, four hundred thirty-five thousand, four hundred forty".