21120645362445 has 64 divisors (see below), whose sum is σ = 37696275267840. Its totient is φ = 11219847300864.

The previous prime is 21120645362431. The next prime is 21120645362459. The reversal of 21120645362445 is 54426354602112.

It is a happy number.

21120645362445 is a `hidden beast` number, since 2 + 1 + 1 + 206 + 45 + 362 + 4 + 45 = 666.

It is an interprime number because it is at equal distance from previous prime (21120645362431) and next prime (21120645362459).

It is not a de Polignac number, because 21120645362445 - 2³⁶ = 21051925885709 is a prime.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21120645362445.

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 63 ways as a sum of consecutive naturals, for example, 73706187 + ... + 73992183.

It is an arithmetic number, because the mean of its divisors is an integer number (589004301060).

Almost surely, 2^{21120645362445} is an apocalyptic number.

It is an amenable number.

21120645362445 is a deficient number, since it is larger than the sum of its proper divisors (16575629905395).

21120645362445 is a wasteful number, since it uses less digits than its factorization.

21120645362445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288171 (or 288165 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 45.

Adding to 21120645362445 its reverse (54426354602112), we get a palindrome (75546999964557).

The spelling of 21120645362445 in words is "twenty-one trillion, one hundred twenty billion, six hundred forty-five million, three hundred sixty-two thousand, four hundred forty-five".