66261504 has 80 divisors (see below), whose sum is σ = 178247520. Its totient is φ = 21872640.

The previous prime is 66261499. The next prime is 66261511. The reversal of 66261504 is 40516266.

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, 274824 + ... + 275064.

It is an arithmetic number, because the mean of its divisors is an integer number (2228094).

Almost surely, 2^66261504 is an apocalyptic number.

66261504 is a gapful number since it is divisible by the number (64) 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 66261504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89123760).

66261504 is an abundant number, since it is smaller than the sum of its proper divisors (111986016).

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

66261504 is a wasteful number, since it uses less digits than its factorization.

66261504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441 (or 425 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 66261504 is about 8140.1169524768. The cubic root of 66261504 is about 404.6570362791.

The spelling of 66261504 in words is "sixty-six million, two hundred sixty-one thousand, five hundred four".