66180780 has 48 divisors (see below), whose sum is σ = 205897440. Its totient is φ = 17648064.

The previous prime is 66180761. The next prime is 66180787. The reversal of 66180780 is 8708166.

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

It is not an unprimeable number, because it can be changed into a prime (66180787) 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, 60739 + ... + 61818.

It is an arithmetic number, because the mean of its divisors is an integer number (4289530).

Almost surely, 2^66180780 is an apocalyptic number.

66180780 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66180780 is an abundant number, since it is smaller than the sum of its proper divisors (139716660).

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

66180780 is a wasteful number, since it uses less digits than its factorization.

66180780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122575 (or 122567 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 66180780 is about 8135.1570359766. The cubic root of 66180780 is about 404.4926431464.

The spelling of 66180780 in words is "sixty-six million, one hundred eighty thousand, seven hundred eighty".