21454444034405 has 4 divisors (see below), whose sum is σ = 25745332841292. Its totient is φ = 17163555227520.

The previous prime is 21454444034381. The next prime is 21454444034459. The reversal of 21454444034405 is 50443044445412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6292461876484 + 15161982157921 = 2508478^2 + 3893839^2 .

It is not a de Polignac number, because 21454444034405 - 2⁶ = 21454444034341 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2145444403436 + ... + 2145444403445.

It is an arithmetic number, because the mean of its divisors is an integer number (6436333210323).

Almost surely, 2^{21454444034405} is an apocalyptic number.

It is an amenable number.

21454444034405 is a deficient number, since it is larger than the sum of its proper divisors (4290888806887).

21454444034405 is an equidigital number, since it uses as much as digits as its factorization.

21454444034405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4290888806886.

The product of its (nonzero) digits is 2457600, while the sum is 44.

Adding to 21454444034405 its reverse (50443044445412), we get a palindrome (71897488479817).

The spelling of 21454444034405 in words is "twenty-one trillion, four hundred fifty-four billion, four hundred forty-four million, thirty-four thousand, four hundred five".