21871081427438 has 16 divisors (see below), whose sum is σ = 34815549716640. Its totient is φ = 10268828791296.

The previous prime is 21871081427369. The next prime is 21871081427453. The reversal of 21871081427438 is 83472418017812.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 732635531 + ... + 732665382.

It is an arithmetic number, because the mean of its divisors is an integer number (2175971857290).

Almost surely, 2^{21871081427438} is an apocalyptic number.

21871081427438 is a deficient number, since it is larger than the sum of its proper divisors (12944468289202).

21871081427438 is a wasteful number, since it uses less digits than its factorization.

21871081427438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1465301371.

The product of its (nonzero) digits is 4816896, while the sum is 56.

The spelling of 21871081427438 in words is "twenty-one trillion, eight hundred seventy-one billion, eighty-one million, four hundred twenty-seven thousand, four hundred thirty-eight".