66503550 has 48 divisors (see below), whose sum is σ = 166275072. Its totient is φ = 17589600.

The previous prime is 66503537. The next prime is 66503579. The reversal of 66503550 is 5530566.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon number.

It is a congruent number.

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, 17305 + ... + 20795.

It is an arithmetic number, because the mean of its divisors is an integer number (3464064).

Almost surely, 2^66503550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66503550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83137536).

66503550 is an abundant number, since it is smaller than the sum of its proper divisors (99771522).

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

66503550 is a wasteful number, since it uses less digits than its factorization.

66503550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3633 (or 3628 counting only the distinct ones).

The product of its (nonzero) digits is 13500, while the sum is 30.

The square root of 66503550 is about 8154.9708767107. The cubic root of 66503550 is about 405.1491601168.

The spelling of 66503550 in words is "sixty-six million, five hundred three thousand, five hundred fifty".