21554610632671 has 2 divisors, whose sum is σ = 21554610632672. Its totient is φ = 21554610632670.

The previous prime is 21554610632663. The next prime is 21554610632677. The reversal of 21554610632671 is 17623601645512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21554610632671 - 2³ = 21554610632663 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21554610632677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10777305316335 + 10777305316336.

It is an arithmetic number, because the mean of its divisors is an integer number (10777305316336).

Almost surely, 2^{21554610632671} is an apocalyptic number.

21554610632671 is a deficient number, since it is larger than the sum of its proper divisors (1).

21554610632671 is an equidigital number, since it uses as much as digits as its factorization.

21554610632671 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1814400, while the sum is 49.

The spelling of 21554610632671 in words is "twenty-one trillion, five hundred fifty-four billion, six hundred ten million, six hundred thirty-two thousand, six hundred seventy-one".