21871386471 has 16 divisors (see below), whose sum is σ = 31870067328. Its totient is φ = 13231576800.

The previous prime is 21871386443. The next prime is 21871386473. The reversal of 21871386471 is 17468317812.

It is not a de Polignac number, because 21871386471 - 2²² = 21867192167 is a prime.

It is a super-3 number, since 3×21871386471³ (a number of 32 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21871386471.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21871386473) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 576565 + ... + 613326.

It is an arithmetic number, because the mean of its divisors is an integer number (1991879208).

Almost surely, 2^21871386471 is an apocalyptic number.

21871386471 is a deficient number, since it is larger than the sum of its proper divisors (9998680857).

21871386471 is a wasteful number, since it uses less digits than its factorization.

21871386471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1190462.

The product of its digits is 451584, while the sum is 48.

The spelling of 21871386471 in words is "twenty-one billion, eight hundred seventy-one million, three hundred eighty-six thousand, four hundred seventy-one".