21454051511 has 2 divisors, whose sum is σ = 21454051512. Its totient is φ = 21454051510.

The previous prime is 21454051501. The next prime is 21454051529. The reversal of 21454051511 is 11515045412.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21454051511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21454051501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10727025755 + 10727025756.

It is an arithmetic number, because the mean of its divisors is an integer number (10727025756).

Almost surely, 2^21454051511 is an apocalyptic number.

21454051511 is a deficient number, since it is larger than the sum of its proper divisors (1).

21454051511 is an equidigital number, since it uses as much as digits as its factorization.

21454051511 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4000, while the sum is 29.

Adding to 21454051511 its reverse (11515045412), we get a palindrome (32969096923).

The spelling of 21454051511 in words is "twenty-one billion, four hundred fifty-four million, fifty-one thousand, five hundred eleven".