21153034044 has 36 divisors (see below), whose sum is σ = 53705741544. Its totient is φ = 7019946912.

The previous prime is 21153033961. The next prime is 21153034069. The reversal of 21153034044 is 44043035112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 21153033999 and 21153034017.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1286067 + ... + 1302410.

It is an arithmetic number, because the mean of its divisors is an integer number (1491826154).

Almost surely, 2^21153034044 is an apocalyptic number.

It is an amenable number.

21153034044 is an abundant number, since it is smaller than the sum of its proper divisors (32552707500).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21153034044 is a wasteful number, since it uses less digits than its factorization.

21153034044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2588714 (or 2588709 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

Adding to 21153034044 its reverse (44043035112), we get a palindrome (65196069156).

The spelling of 21153034044 in words is "twenty-one billion, one hundred fifty-three million, thirty-four thousand, forty-four".