21843631556 has 24 divisors (see below), whose sum is σ = 39490649856. Its totient is φ = 10561145760.

The previous prime is 21843631531. The next prime is 21843631559. The reversal of 21843631556 is 65513634812.

It is a happy number.

It is a super-2 number, since 2×21843631556² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21843631559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89375 + ... + 227321.

It is an arithmetic number, because the mean of its divisors is an integer number (1645443744).

Almost surely, 2^21843631556 is an apocalyptic number.

It is an amenable number.

21843631556 is a deficient number, since it is larger than the sum of its proper divisors (17647018300).

21843631556 is a wasteful number, since it uses less digits than its factorization.

21843631556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139259 (or 139257 counting only the distinct ones).

The product of its digits is 518400, while the sum is 44.

The spelling of 21843631556 in words is "twenty-one billion, eight hundred forty-three million, six hundred thirty-one thousand, five hundred fifty-six".