21534204055 has 32 divisors (see below), whose sum is σ = 32663965824. Its totient is φ = 13262040576.

The previous prime is 21534204053. The next prime is 21534204067. The reversal of 21534204055 is 55040243512.

It is a cyclic number.

It is not a de Polignac number, because 21534204055 - 2¹ = 21534204053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21534204053) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 622732 + ... + 656401.

It is an arithmetic number, because the mean of its divisors is an integer number (1020748932).

Almost surely, 2^21534204055 is an apocalyptic number.

21534204055 is a deficient number, since it is larger than the sum of its proper divisors (11129761769).

21534204055 is a wasteful number, since it uses less digits than its factorization.

21534204055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1279195.

The product of its (nonzero) digits is 24000, while the sum is 31.

Adding to 21534204055 its reverse (55040243512), we get a palindrome (76574447567).

The spelling of 21534204055 in words is "twenty-one billion, five hundred thirty-four million, two hundred four thousand, fifty-five".