21054444451 has 2 divisors, whose sum is σ = 21054444452. Its totient is φ = 21054444450.

The previous prime is 21054444419. The next prime is 21054444493. The reversal of 21054444451 is 15444445012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21054444451 - 2⁵ = 21054444419 is a prime.

It is a super-2 number, since 2×21054444451² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21054444401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10527222225 + 10527222226.

It is an arithmetic number, because the mean of its divisors is an integer number (10527222226).

Almost surely, 2^21054444451 is an apocalyptic number.

21054444451 is a deficient number, since it is larger than the sum of its proper divisors (1).

21054444451 is an equidigital number, since it uses as much as digits as its factorization.

21054444451 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51200, while the sum is 34.

Adding to 21054444451 its reverse (15444445012), we get a palindrome (36498889463).

The spelling of 21054444451 in words is "twenty-one billion, fifty-four million, four hundred forty-four thousand, four hundred fifty-one".