66563280 has 240 divisors, whose sum is σ = 261840384. Its totient is φ = 14837760.

The previous prime is 66563249. The next prime is 66563303. The reversal of 66563280 is 8236566.

It is a tau number, because it is divible by the number of its divisors (240).

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, 236740 + ... + 237020.

Almost surely, 2^66563280 is an apocalyptic number.

66563280 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 66563280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130920192).

66563280 is an abundant number, since it is smaller than the sum of its proper divisors (195277104).

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

66563280 is a wasteful number, since it uses less digits than its factorization.

66563280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354 (or 345 counting only the distinct ones).

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

The square root of 66563280 is about 8158.6322383105. The cubic root of 66563280 is about 405.2704183956.

The spelling of 66563280 in words is "sixty-six million, five hundred sixty-three thousand, two hundred eighty".