21871905596 has 12 divisors (see below), whose sum is σ = 38414016648. Its totient is φ = 10896472272.

The previous prime is 21871905563. The next prime is 21871905617. The reversal of 21871905596 is 69550917812.

It is a happy number.

It is a super-2 number, since 2×21871905596² (a number of 21 digits) contains 22 as substring.

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 3 ways as a sum of consecutive naturals, for example, 9868886 + ... + 9871101.

It is an arithmetic number, because the mean of its divisors is an integer number (3201168054).

Almost surely, 2^21871905596 is an apocalyptic number.

It is an amenable number.

21871905596 is a deficient number, since it is larger than the sum of its proper divisors (16542111052).

21871905596 is a wasteful number, since it uses less digits than its factorization.

21871905596 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19740268 (or 19740266 counting only the distinct ones).

The product of its (nonzero) digits is 1360800, while the sum is 53.

The spelling of 21871905596 in words is "twenty-one billion, eight hundred seventy-one million, nine hundred five thousand, five hundred ninety-six".