21548370671 has 2 divisors, whose sum is σ = 21548370672. Its totient is φ = 21548370670.

The previous prime is 21548370667. The next prime is 21548370713. The reversal of 21548370671 is 17607384512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21548370671 - 2² = 21548370667 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21548370271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10774185335 + 10774185336.

It is an arithmetic number, because the mean of its divisors is an integer number (10774185336).

Almost surely, 2^21548370671 is an apocalyptic number.

21548370671 is a deficient number, since it is larger than the sum of its proper divisors (1).

21548370671 is an equidigital number, since it uses as much as digits as its factorization.

21548370671 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282240, while the sum is 44.

The spelling of 21548370671 in words is "twenty-one billion, five hundred forty-eight million, three hundred seventy thousand, six hundred seventy-one".