66724140 has 48 divisors (see below), whose sum is σ = 213518592. Its totient is φ = 15251136.

The previous prime is 66724129. The next prime is 66724159. The reversal of 66724140 is 4142766.

66724140 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×66724140² = 8904221717479200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 66724098 and 66724107.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79014 + ... + 79853.

It is an arithmetic number, because the mean of its divisors is an integer number (4448304).

Almost surely, 2^66724140 is an apocalyptic number.

66724140 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66724140 is an abundant number, since it is smaller than the sum of its proper divisors (146794452).

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

66724140 is a wasteful number, since it uses less digits than its factorization.

66724140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158886 (or 158884 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 30.

The square root of 66724140 is about 8168.4845595741. The cubic root of 66724140 is about 405.5966210441.

It can be divided in two parts, 66 and 724140, that added together give a triangular number (724206 = T₁₂₀₃).

The spelling of 66724140 in words is "sixty-six million, seven hundred twenty-four thousand, one hundred forty".