66819822 has 32 divisors (see below), whose sum is σ = 135475200. Its totient is φ = 21970080.

The previous prime is 66819821. The next prime is 66819871. The reversal of 66819822 is 22891866.

66819822 = 324² + 325² + ... + 616².

It is a super-3 number, since 3×66819822³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66819821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 227908 + ... + 228200.

It is an arithmetic number, because the mean of its divisors is an integer number (4233600).

Almost surely, 2^66819822 is an apocalyptic number.

66819822 is an abundant number, since it is smaller than the sum of its proper divisors (68655378).

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

66819822 is a wasteful number, since it uses less digits than its factorization.

66819822 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688.

The product of its digits is 82944, while the sum is 42.

The square root of 66819822 is about 8174.3392393514. The cubic root of 66819822 is about 405.7904027867.

The spelling of 66819822 in words is "sixty-six million, eight hundred nineteen thousand, eight hundred twenty-two".