66941816450 has 12 divisors (see below), whose sum is σ = 124511778690. Its totient is φ = 26776726560.

The previous prime is 66941816401. The next prime is 66941816467. The reversal of 66941816450 is 5461814966.

It can be written as a sum of positive squares in 3 ways, for example, as 64557154561 + 2384661889 = 254081^2 + 48833^2 .

It is a super-3 number, since 3×66941816450³ (a number of 33 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (50), and also a Moran number because the ratio is a prime number: 1338836329 = 66941816450 / (6 + 6 + 9 + 4 + 1 + 8 + 1 + 6 + 4 + 5 + 0).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 669418115 + ... + 669418214.

Almost surely, 2^66941816450 is an apocalyptic number.

66941816450 is a deficient number, since it is larger than the sum of its proper divisors (57569962240).

66941816450 is a wasteful number, since it uses less digits than its factorization.

66941816450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1338836341 (or 1338836336 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 50.

The spelling of 66941816450 in words is "sixty-six billion, nine hundred forty-one million, eight hundred sixteen thousand, four hundred fifty".