21444001949651 has 2 divisors, whose sum is σ = 21444001949652. Its totient is φ = 21444001949650.

The previous prime is 21444001949611. The next prime is 21444001949683. The reversal of 21444001949651 is 15694910044412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21444001949651 - 2¹⁴ = 21444001933267 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21444001949651.

It is not a weakly prime, because it can be changed into another prime (21444001949611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10722000974825 + 10722000974826.

It is an arithmetic number, because the mean of its divisors is an integer number (10722000974826).

Almost surely, 2^{21444001949651} is an apocalyptic number.

21444001949651 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444001949651 is an equidigital number, since it uses as much as digits as its factorization.

21444001949651 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1244160, while the sum is 50.

The spelling of 21444001949651 in words is "twenty-one trillion, four hundred forty-four billion, one million, nine hundred forty-nine thousand, six hundred fifty-one".