21155143645087 has 2 divisors, whose sum is σ = 21155143645088. Its totient is φ = 21155143645086.

The previous prime is 21155143645039. The next prime is 21155143645169. The reversal of 21155143645087 is 78054634155112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21155143645087 - 2¹⁹ = 21155143120799 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21155143615087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10577571822543 + 10577571822544.

It is an arithmetic number, because the mean of its divisors is an integer number (10577571822544).

Almost surely, 2^{21155143645087} is an apocalyptic number.

21155143645087 is a deficient number, since it is larger than the sum of its proper divisors (1).

21155143645087 is an equidigital number, since it uses as much as digits as its factorization.

21155143645087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032000, while the sum is 52.

The spelling of 21155143645087 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred forty-three million, six hundred forty-five thousand, eighty-seven".