66040544 has 48 divisors (see below), whose sum is σ = 138311712. Its totient is φ = 30970368.

The previous prime is 66040543. The next prime is 66040573. The reversal of 66040544 is 44504066.

It is a super-2 number, since 2×66040544² = 8722706903631872, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66040543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38162 + ... + 39854.

It is an arithmetic number, because the mean of its divisors is an integer number (2881494).

Almost surely, 2^66040544 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66040544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69155856).

66040544 is an abundant number, since it is smaller than the sum of its proper divisors (72271168).

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

66040544 is a wasteful number, since it uses less digits than its factorization.

66040544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1779 (or 1771 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 29.

The square root of 66040544 is about 8126.5333322395. The cubic root of 66040544 is about 404.2067366562.

The spelling of 66040544 in words is "sixty-six million, forty thousand, five hundred forty-four".