21018403403752 has 16 divisors (see below), whose sum is σ = 39908360894400. Its totient is φ = 10376173831920.

The previous prime is 21018403403707. The next prime is 21018403403761. The reversal of 21018403403752 is 25730430481012.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16628483074 + ... + 16628484337.

It is an arithmetic number, because the mean of its divisors is an integer number (2494272555900).

Almost surely, 2^{21018403403752} is an apocalyptic number.

It is an amenable number.

21018403403752 is a deficient number, since it is larger than the sum of its proper divisors (18889957490648).

21018403403752 is a wasteful number, since it uses less digits than its factorization.

21018403403752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33256967496 (or 33256967492 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 40.

Adding to 21018403403752 its reverse (25730430481012), we get a palindrome (46748833884764).

The spelling of 21018403403752 in words is "twenty-one trillion, eighteen billion, four hundred three million, four hundred three thousand, seven hundred fifty-two".