66451536 has 80 divisors (see below), whose sum is σ = 192755520. Its totient is φ = 21916800.

The previous prime is 66451501. The next prime is 66451537. The reversal of 66451536 is 63515466.

66451536 is a `hidden beast` number, since 6 + 645 + 1 + 5 + 3 + 6 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 66451536.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66451537) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42871 + ... + 44393.

It is an arithmetic number, because the mean of its divisors is an integer number (2409444).

Almost surely, 2^66451536 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 66451536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96377760).

66451536 is an abundant number, since it is smaller than the sum of its proper divisors (126303984).

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

66451536 is a wasteful number, since it uses less digits than its factorization.

66451536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1641 (or 1629 counting only the distinct ones).

The product of its digits is 64800, while the sum is 36.

The square root of 66451536 is about 8151.7811550605. The cubic root of 66451536 is about 405.0435069859.

The spelling of 66451536 in words is "sixty-six million, four hundred fifty-one thousand, five hundred thirty-six".