21216026522645 has 8 divisors (see below), whose sum is σ = 25781500584960. Its totient is φ = 16757975379600.

The previous prime is 21216026522629. The next prime is 21216026522651. The reversal of 21216026522645 is 54622562061212.

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

It is not a de Polignac number, because 21216026522645 - 2⁴ = 21216026522629 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21216026522596 and 21216026522605.

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, 26855729381 + ... + 26855730170.

It is an arithmetic number, because the mean of its divisors is an integer number (3222687573120).

Almost surely, 2^{21216026522645} is an apocalyptic number.

It is an amenable number.

21216026522645 is a deficient number, since it is larger than the sum of its proper divisors (4565474062315).

21216026522645 is an equidigital number, since it uses as much as digits as its factorization.

21216026522645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53711459635.

The product of its (nonzero) digits is 691200, while the sum is 44.

Adding to 21216026522645 its reverse (54622562061212), we get a palindrome (75838588583857).

The spelling of 21216026522645 in words is "twenty-one trillion, two hundred sixteen billion, twenty-six million, five hundred twenty-two thousand, six hundred forty-five".