21871347623 has 16 divisors (see below), whose sum is σ = 22532864256. Its totient is φ = 21216192960.

The previous prime is 21871347599. The next prime is 21871347647. The reversal of 21871347623 is 32674317812.

It is an interprime number because it is at equal distance from previous prime (21871347599) and next prime (21871347647).

It is a cyclic number.

It is not a de Polignac number, because 21871347623 - 2²⁴ = 21854570407 is a prime.

It is a super-2 number, since 2×21871347623² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21871347653) 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, 14173790 + ... + 14175332.

It is an arithmetic number, because the mean of its divisors is an integer number (1408304016).

Almost surely, 2^21871347623 is an apocalyptic number.

21871347623 is a deficient number, since it is larger than the sum of its proper divisors (661516633).

21871347623 is a wasteful number, since it uses less digits than its factorization.

21871347623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3334.

The product of its digits is 338688, while the sum is 44.

The spelling of 21871347623 in words is "twenty-one billion, eight hundred seventy-one million, three hundred forty-seven thousand, six hundred twenty-three".