66996720 has 300 divisors, whose sum is σ = 271962504. Its totient is φ = 15240960.

The previous prime is 66996707. The next prime is 66996731. The reversal of 66996720 is 2769966.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 317415 + ... + 317625.

Almost surely, 2^66996720 is an apocalyptic number.

66996720 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 66996720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135981252).

66996720 is an abundant number, since it is smaller than the sum of its proper divisors (204965784).

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

66996720 is a wasteful number, since it uses less digits than its factorization.

66996720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 228 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 66996720 is about 8185.1524115315. The cubic root of 66996720 is about 406.1481821365.

The spelling of 66996720 in words is "sixty-six million, nine hundred ninety-six thousand, seven hundred twenty".