21151144545 has 16 divisors (see below), whose sum is σ = 33872539392. Its totient is φ = 11270374400.

The previous prime is 21151144543. The next prime is 21151144559. The reversal of 21151144545 is 54544115112.

It is not a de Polignac number, because 21151144545 - 2¹ = 21151144543 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21151144543) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 622656 + ... + 655745.

It is an arithmetic number, because the mean of its divisors is an integer number (2117033712).

Almost surely, 2^21151144545 is an apocalyptic number.

It is an amenable number.

21151144545 is a deficient number, since it is larger than the sum of its proper divisors (12721394847).

21151144545 is a wasteful number, since it uses less digits than its factorization.

21151144545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1279512.

The product of its digits is 16000, while the sum is 33.

Adding to 21151144545 its reverse (54544115112), we get a palindrome (75695259657).

The spelling of 21151144545 in words is "twenty-one billion, one hundred fifty-one million, one hundred forty-four thousand, five hundred forty-five".