21216030011455 has 8 divisors (see below), whose sum is σ = 25817816803104. Its totient is φ = 16733770149600.

The previous prime is 21216030011441. The next prime is 21216030011489. The reversal of 21216030011455 is 55411003061212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21216030011455 - 2⁹ = 21216030010943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29881732056 + ... + 29881732765.

It is an arithmetic number, because the mean of its divisors is an integer number (3227227100388).

Almost surely, 2^{21216030011455} is an apocalyptic number.

21216030011455 is a deficient number, since it is larger than the sum of its proper divisors (4601786791649).

21216030011455 is an equidigital number, since it uses as much as digits as its factorization.

21216030011455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59763464897.

The product of its (nonzero) digits is 7200, while the sum is 31.

Adding to 21216030011455 its reverse (55411003061212), we get a palindrome (76627033072667).

The spelling of 21216030011455 in words is "twenty-one trillion, two hundred sixteen billion, thirty million, eleven thousand, four hundred fifty-five".