21612065044 has 12 divisors (see below), whose sum is σ = 37822322944. Its totient is φ = 10805687064.

The previous prime is 21612065029. The next prime is 21612065063. The reversal of 21612065044 is 44056021612.

It is a happy number.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21612064997 and 21612065015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98239 + ... + 229945.

Almost surely, 2^21612065044 is an apocalyptic number.

It is an amenable number.

21612065044 is a deficient number, since it is larger than the sum of its proper divisors (16210257900).

21612065044 is a wasteful number, since it uses less digits than its factorization.

21612065044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172734 (or 172732 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

Adding to 21612065044 its reverse (44056021612), we get a palindrome (65668086656).

The spelling of 21612065044 in words is "twenty-one billion, six hundred twelve million, sixty-five thousand, forty-four".