21506044534 has 32 divisors (see below), whose sum is σ = 35137025280. Its totient is φ = 9812880000.

The previous prime is 21506044523. The next prime is 21506044541. The reversal of 21506044534 is 43544060512.

It is a self number, because there is not a number n which added to its sum of digits gives 21506044534.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1856059 + ... + 1867609.

It is an arithmetic number, because the mean of its divisors is an integer number (1098032040).

Almost surely, 2^21506044534 is an apocalyptic number.

21506044534 is a deficient number, since it is larger than the sum of its proper divisors (13630980746).

21506044534 is a wasteful number, since it uses less digits than its factorization.

21506044534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12376.

The product of its (nonzero) digits is 57600, while the sum is 34.

The spelling of 21506044534 in words is "twenty-one billion, five hundred six million, forty-four thousand, five hundred thirty-four".