1780540055221 has 2 divisors, whose sum is σ = 1780540055222. Its totient is φ = 1780540055220.

The previous prime is 1780540055209. The next prime is 1780540055297. The reversal of 1780540055221 is 1225500450871.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1638873634225 + 141666420996 = 1280185^2 + 376386^2 .

It is a cyclic number.

It is not a de Polignac number, because 1780540055221 - 2³¹ = 1778392571573 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1780540055821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 890270027610 + 890270027611.

It is an arithmetic number, because the mean of its divisors is an integer number (890270027611).

Almost surely, 2^{1780540055221} is an apocalyptic number.

It is an amenable number.

1780540055221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1780540055221 is an equidigital number, since it uses as much as digits as its factorization.

1780540055221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112000, while the sum is 40.

The spelling of 1780540055221 in words is "one trillion, seven hundred eighty billion, five hundred forty million, fifty-five thousand, two hundred twenty-one".