381286555621 has 2 divisors, whose sum is σ = 381286555622. Its totient is φ = 381286555620.

The previous prime is 381286555549. The next prime is 381286555631. The reversal of 381286555621 is 126555682183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 319180931521 + 62105624100 = 564961^2 + 249210^2 .

It is a cyclic number.

It is not a de Polignac number, because 381286555621 - 2¹⁵ = 381286522853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (381286555631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190643277810 + 190643277811.

It is an arithmetic number, because the mean of its divisors is an integer number (190643277811).

Almost surely, 2^381286555621 is an apocalyptic number.

It is an amenable number.

381286555621 is a deficient number, since it is larger than the sum of its proper divisors (1).

381286555621 is an equidigital number, since it uses as much as digits as its factorization.

381286555621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456000, while the sum is 52.

The spelling of 381286555621 in words is "three hundred eighty-one billion, two hundred eighty-six million, five hundred fifty-five thousand, six hundred twenty-one".