16551454511021 has 2 divisors, whose sum is σ = 16551454511022. Its totient is φ = 16551454511020.

The previous prime is 16551454510973. The next prime is 16551454511159. The reversal of 16551454511021 is 12011545415561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13422411922921 + 3129042588100 = 3663661^2 + 1768910^2 .

It is a cyclic number.

It is not a de Polignac number, because 16551454511021 - 2²² = 16551450316717 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16551454511021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16551454517021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8275727255510 + 8275727255511.

It is an arithmetic number, because the mean of its divisors is an integer number (8275727255511).

Almost surely, 2^{16551454511021} is an apocalyptic number.

It is an amenable number.

16551454511021 is a deficient number, since it is larger than the sum of its proper divisors (1).

16551454511021 is an equidigital number, since it uses as much as digits as its factorization.

16551454511021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120000, while the sum is 41.

Adding to 16551454511021 its reverse (12011545415561), we get a palindrome (28562999926582).

The spelling of 16551454511021 in words is "sixteen trillion, five hundred fifty-one billion, four hundred fifty-four million, five hundred eleven thousand, twenty-one".