66623444401 has 8 divisors (see below), whose sum is σ = 67328131304. Its totient is φ = 65919121920.

The previous prime is 66623444399. The next prime is 66623444429. The reversal of 66623444401 is 10444432666.

It can be written as a sum of positive squares in 4 ways, for example, as 22921960000 + 43701484401 = 151400^2 + 209049^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66623444401 - 2¹ = 66623444399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66621444401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 284611 + ... + 462871.

It is an arithmetic number, because the mean of its divisors is an integer number (8416016413).

Almost surely, 2^66623444401 is an apocalyptic number.

It is an amenable number.

66623444401 is a deficient number, since it is larger than the sum of its proper divisors (704686903).

66623444401 is a wasteful number, since it uses less digits than its factorization.

66623444401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182211.

The product of its (nonzero) digits is 331776, while the sum is 40.

The spelling of 66623444401 in words is "sixty-six billion, six hundred twenty-three million, four hundred forty-four thousand, four hundred one".