66544740 has 60 divisors (see below), whose sum is σ = 208758396. Its totient is φ = 17744832.

The previous prime is 66544703. The next prime is 66544769. The reversal of 66544740 is 4744566.

It can be written as a sum of positive squares in 2 ways, for example, as 45805824 + 20738916 = 6768^2 + 4554^2 .

It is a tau number, because it is divible by the number of its divisors (60).

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

It is a junction number, because it is equal to n+sod(n) for n = 66544695 and 66544704.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 18919 + ... + 22158.

Almost surely, 2^66544740 is an apocalyptic number.

66544740 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66544740 is an abundant number, since it is smaller than the sum of its proper divisors (142213656).

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

66544740 is a wasteful number, since it uses less digits than its factorization.

66544740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41098 (or 41087 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 36.

The square root of 66544740 is about 8157.4959393186. The cubic root of 66544740 is about 405.2327879820.

The spelling of 66544740 in words is "sixty-six million, five hundred forty-four thousand, seven hundred forty".