66123780 has 24 divisors (see below), whose sum is σ = 185146752. Its totient is φ = 17632992.

The previous prime is 66123779. The next prime is 66123803. The reversal of 66123780 is 8732166.

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, 550972 + ... + 551091.

It is an arithmetic number, because the mean of its divisors is an integer number (7714448).

Almost surely, 2^66123780 is an apocalyptic number.

66123780 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66123780 is an abundant number, since it is smaller than the sum of its proper divisors (119022972).

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

66123780 is a wasteful number, since it uses less digits than its factorization.

66123780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1102075 (or 1102073 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 66123780 is about 8131.6529684929. The cubic root of 66123780 is about 404.3764830213.

The spelling of 66123780 in words is "sixty-six million, one hundred twenty-three thousand, seven hundred eighty".