21154325250645 has 24 divisors (see below), whose sum is σ = 36829027943136. Its totient is φ = 11232605002848.

The previous prime is 21154325250631. The next prime is 21154325250659. The reversal of 21154325250645 is 54605252345112.

21154325250645 is a `hidden beast` number, since 2 + 1 + 1 + 54 + 3 + 2 + 52 + 506 + 45 = 666.

It is an interprime number because it is at equal distance from previous prime (21154325250631) and next prime (21154325250659).

It is not a de Polignac number, because 21154325250645 - 2⁵ = 21154325250613 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 21154325250645.

It is a congruent number.

It is an unprimeable number.

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 in 23 ways as a sum of consecutive naturals, for example, 1035443787 + ... + 1035464216.

It is an arithmetic number, because the mean of its divisors is an integer number (1534542830964).

Almost surely, 2^{21154325250645} is an apocalyptic number.

It is an amenable number.

21154325250645 is a deficient number, since it is larger than the sum of its proper divisors (15674702692491).

21154325250645 is a wasteful number, since it uses less digits than its factorization.

21154325250645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2070908241 (or 2070908238 counting only the distinct ones).

The product of its (nonzero) digits is 1440000, while the sum is 45.

Adding to 21154325250645 its reverse (54605252345112), we get a palindrome (75759577595757).

The spelling of 21154325250645 in words is "twenty-one trillion, one hundred fifty-four billion, three hundred twenty-five million, two hundred fifty thousand, six hundred forty-five".