21154524322065 has 16 divisors (see below), whose sum is σ = 33848622772800. Its totient is φ = 11281951685952.

The previous prime is 21154524322049. The next prime is 21154524322109. The reversal of 21154524322065 is 56022342545112.

It is not a de Polignac number, because 21154524322065 - 2⁴ = 21154524322049 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28451095 + ... + 29185164.

It is an arithmetic number, because the mean of its divisors is an integer number (2115538923300).

Almost surely, 2^{21154524322065} is an apocalyptic number.

It is an amenable number.

21154524322065 is a deficient number, since it is larger than the sum of its proper divisors (12694098450735).

21154524322065 is a wasteful number, since it uses less digits than its factorization.

21154524322065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57660736.

The product of its (nonzero) digits is 576000, while the sum is 42.

Adding to 21154524322065 its reverse (56022342545112), we get a palindrome (77176866867177).

The spelling of 21154524322065 in words is "twenty-one trillion, one hundred fifty-four billion, five hundred twenty-four million, three hundred twenty-two thousand, sixty-five".