66544920 has 192 divisors, whose sum is σ = 237837600. Its totient is φ = 16035840.

The previous prime is 66544883. The next prime is 66544931. The reversal of 66544920 is 2944566.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 276000 + ... + 276240.

Almost surely, 2^66544920 is an apocalyptic number.

66544920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66544920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118918800).

66544920 is an abundant number, since it is smaller than the sum of its proper divisors (171292680).

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

66544920 is a wasteful number, since it uses less digits than its factorization.

66544920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330 (or 323 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 66544920 is about 8157.5069721086. The cubic root of 66544920 is about 405.2331533594.

The spelling of 66544920 in words is "sixty-six million, five hundred forty-four thousand, nine hundred twenty".