21612355455023 has 4 divisors (see below), whose sum is σ = 21612624523080. Its totient is φ = 21612086386968.

The previous prime is 21612355454993. The next prime is 21612355455091. The reversal of 21612355455023 is 32055455321612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21612355455023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21612355355023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 134413508 + ... + 134574201.

It is an arithmetic number, because the mean of its divisors is an integer number (5403156130770).

Almost surely, 2^{21612355455023} is an apocalyptic number.

21612355455023 is a deficient number, since it is larger than the sum of its proper divisors (269068057).

21612355455023 is an equidigital number, since it uses as much as digits as its factorization.

21612355455023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269068056.

The product of its (nonzero) digits is 1080000, while the sum is 44.

The spelling of 21612355455023 in words is "twenty-one trillion, six hundred twelve billion, three hundred fifty-five million, four hundred fifty-five thousand, twenty-three".