64220940181 has 2 divisors, whose sum is σ = 64220940182. Its totient is φ = 64220940180.

The previous prime is 64220940127. The next prime is 64220940227. The reversal of 64220940181 is 18104902246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53162524900 + 11058415281 = 230570^2 + 105159^2 .

It is a cyclic number.

It is not a de Polignac number, because 64220940181 - 2¹⁹ = 64220415893 is a prime.

It is a super-2 number, since 2×64220940181² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 64220940181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64220940281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32110470090 + 32110470091.

It is an arithmetic number, because the mean of its divisors is an integer number (32110470091).

Almost surely, 2^64220940181 is an apocalyptic number.

It is an amenable number.

64220940181 is a deficient number, since it is larger than the sum of its proper divisors (1).

64220940181 is an equidigital number, since it uses as much as digits as its factorization.

64220940181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 37.

The spelling of 64220940181 in words is "sixty-four billion, two hundred twenty million, nine hundred forty thousand, one hundred eighty-one".