66219054401 has 16 divisors (see below), whose sum is σ = 70455050640. Its totient is φ = 62118201600.

The previous prime is 66219054371. The next prime is 66219054431. The reversal of 66219054401 is 10445091266.

It is an interprime number because it is at equal distance from previous prime (66219054371) and next prime (66219054431).

It can be written as a sum of positive squares in 8 ways, for example, as 19021926400 + 47197128001 = 137920^2 + 217249^2 .

It is a cyclic number.

It is not a de Polignac number, because 66219054401 - 2¹⁰ = 66219053377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66219054431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 708155 + ... + 796191.

It is an arithmetic number, because the mean of its divisors is an integer number (4403440665).

Almost surely, 2^66219054401 is an apocalyptic number.

It is an amenable number.

66219054401 is a deficient number, since it is larger than the sum of its proper divisors (4235996239).

66219054401 is a wasteful number, since it uses less digits than its factorization.

66219054401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88804.

The product of its (nonzero) digits is 51840, while the sum is 38.

The spelling of 66219054401 in words is "sixty-six billion, two hundred nineteen million, fifty-four thousand, four hundred one".