66116570520 has 512 divisors, whose sum is σ = 267875112960. Its totient is φ = 12607488000.

The previous prime is 66116570503. The next prime is 66116570537. The reversal of 66116570520 is 2507561166.

It is an interprime number because it is at equal distance from previous prime (66116570503) and next prime (66116570537).

It is a super-2 number, since 2×66116570520² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 21740200 + ... + 21743240.

It is an arithmetic number, because the mean of its divisors is an integer number (523193580).

Almost surely, 2^66116570520 is an apocalyptic number.

66116570520 is a gapful number since it is divisible by the number (60) 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 66116570520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133937556480).

66116570520 is an abundant number, since it is smaller than the sum of its proper divisors (201758542440).

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

66116570520 is a wasteful number, since it uses less digits than its factorization.

66116570520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3267 (or 3263 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 39.

It can be divided in two parts, 66116 and 570520, that added together give a palindrome (636636).

The spelling of 66116570520 in words is "sixty-six billion, one hundred sixteen million, five hundred seventy thousand, five hundred twenty".