21541611136 has 16 divisors (see below), whose sum is σ = 42914928690. Its totient is φ = 10770805504.

The previous prime is 21541611121. The next prime is 21541611139. The reversal of 21541611136 is 63111614512.

It can be written as a sum of positive squares in only one way, i.e., 19165633600 + 2375977536 = 138440^2 + 48744^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a junction number, because it is equal to n+sod(n) for n = 21541611098 and 21541611107.

It is not an unprimeable number, because it can be changed into a prime (21541611139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84146791 + ... + 84147046.

Almost surely, 2^21541611136 is an apocalyptic number.

It is an amenable number.

21541611136 is a deficient number, since it is larger than the sum of its proper divisors (21373317554).

21541611136 is an equidigital number, since it uses as much as digits as its factorization.

21541611136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168293851 (or 168293839 counting only the distinct ones).

The product of its digits is 4320, while the sum is 31.

The spelling of 21541611136 in words is "twenty-one billion, five hundred forty-one million, six hundred eleven thousand, one hundred thirty-six".