21216015265433 has 2 divisors, whose sum is σ = 21216015265434. Its totient is φ = 21216015265432.

The previous prime is 21216015265369. The next prime is 21216015265451. The reversal of 21216015265433 is 33456251061212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13952974095424 + 7263041170009 = 3735368^2 + 2695003^2 .

It is a cyclic number.

It is not a de Polignac number, because 21216015265433 - 2⁶ = 21216015265369 is a prime.

It is not a weakly prime, because it can be changed into another prime (21216015265453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10608007632716 + 10608007632717.

It is an arithmetic number, because the mean of its divisors is an integer number (10608007632717).

Almost surely, 2^{21216015265433} is an apocalyptic number.

It is an amenable number.

21216015265433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21216015265433 is an equidigital number, since it uses as much as digits as its factorization.

21216015265433 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 259200, while the sum is 41.

The spelling of 21216015265433 in words is "twenty-one trillion, two hundred sixteen billion, fifteen million, two hundred sixty-five thousand, four hundred thirty-three".