66020040 has 48 divisors (see below), whose sum is σ = 214566300. Its totient is φ = 17605248.

The previous prime is 66020029. The next prime is 66020077. The reversal of 66020040 is 4002066.

66020040 is a `hidden beast` number, since 660 + 2 + 0 + 0 + 4 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 61685316 + 4334724 = 7854^2 + 2082^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 66019995 and 66020022.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 91335 + ... + 92054.

Almost surely, 2^66020040 is an apocalyptic number.

66020040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66020040 is an abundant number, since it is smaller than the sum of its proper divisors (148546260).

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

66020040 is a wasteful number, since it uses less digits than its factorization.

66020040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183406 (or 183399 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 66020040 is about 8125.2716877653. The cubic root of 66020040 is about 404.1649001706.

The spelling of 66020040 in words is "sixty-six million, twenty thousand, forty".