66905280 has 168 divisors, whose sum is σ = 247966992. Its totient is φ = 16459776.

The previous prime is 66905273. The next prime is 66905297. The reversal of 66905280 is 8250966.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36547 + ... + 38333.

It is an arithmetic number, because the mean of its divisors is an integer number (1475994).

Almost surely, 2^66905280 is an apocalyptic number.

66905280 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 66905280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123983496).

66905280 is an abundant number, since it is smaller than the sum of its proper divisors (181061712).

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

66905280 is a wasteful number, since it uses less digits than its factorization.

66905280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1823 (or 1810 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 66905280 is about 8179.5647805980. The cubic root of 66905280 is about 405.9633218502.

The spelling of 66905280 in words is "sixty-six million, nine hundred five thousand, two hundred eighty".