21213364026641 has 8 divisors (see below), whose sum is σ = 21730995673800. Its totient is φ = 20695743452160.

The previous prime is 21213364026623. The next prime is 21213364026649. The reversal of 21213364026641 is 14662046331212.

It can be written as a sum of positive squares in 4 ways, for example, as 538873446400 + 20674490580241 = 734080^2 + 4546921^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21213364026641 - 2¹⁸ = 21213363764497 is a prime.

It is a super-2 number, since 2×21213364026641² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213364026649) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1178045 + ... + 6619253.

It is an arithmetic number, because the mean of its divisors is an integer number (2716374459225).

Almost surely, 2^{21213364026641} is an apocalyptic number.

It is an amenable number.

21213364026641 is a deficient number, since it is larger than the sum of its proper divisors (517631647159).

21213364026641 is an equidigital number, since it uses as much as digits as its factorization.

21213364026641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5536339.

The product of its (nonzero) digits is 248832, while the sum is 41.

The spelling of 21213364026641 in words is "twenty-one trillion, two hundred thirteen billion, three hundred sixty-four million, twenty-six thousand, six hundred forty-one".