66503351 has 4 divisors (see below), whose sum is σ = 68796600. Its totient is φ = 64210104.

The previous prime is 66503347. The next prime is 66503369. The reversal of 66503351 is 15330566.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66503351 - 2² = 66503347 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 2293219 = 66503351 / (6 + 6 + 5 + 0 + 3 + 3 + 5 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66503251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1146581 + ... + 1146638.

It is an arithmetic number, because the mean of its divisors is an integer number (17199150).

Almost surely, 2^66503351 is an apocalyptic number.

66503351 is a deficient number, since it is larger than the sum of its proper divisors (2293249).

66503351 is a wasteful number, since it uses less digits than its factorization.

66503351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2293248.

The product of its (nonzero) digits is 8100, while the sum is 29.

The square root of 66503351 is about 8154.9586755544. The cubic root of 66503351 is about 405.1487560042.

It can be divided in two parts, 6650 and 3351, that added together give a palindrome (10001).

The spelling of 66503351 in words is "sixty-six million, five hundred three thousand, three hundred fifty-one".