21135300023555 has 16 divisors (see below), whose sum is σ = 25788362721888. Its totient is φ = 16624458144000.

The previous prime is 21135300023549. The next prime is 21135300023569. The reversal of 21135300023555 is 55532000353112.

It is not a de Polignac number, because 21135300023555 - 2³⁴ = 21118120154371 is a prime.

It is a Duffinian 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, 12974861 + ... + 14512670.

It is an arithmetic number, because the mean of its divisors is an integer number (1611772670118).

Almost surely, 2^{21135300023555} is an apocalyptic number.

21135300023555 is a deficient number, since it is larger than the sum of its proper divisors (4653062698333).

21135300023555 is a wasteful number, since it uses less digits than its factorization.

21135300023555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27490118.

The product of its (nonzero) digits is 67500, while the sum is 35.

Adding to 21135300023555 its reverse (55532000353112), we get a palindrome (76667300376667).

The spelling of 21135300023555 in words is "twenty-one trillion, one hundred thirty-five billion, three hundred million, twenty-three thousand, five hundred fifty-five".