21128454736392 has 64 divisors (see below), whose sum is σ = 54007793049600. Its totient is φ = 6884946319680.

The previous prime is 21128454736391. The next prime is 21128454736393. The reversal of 21128454736392 is 29363745482112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21128454736391) and next prime (21128454736393).

It is not an unprimeable number, because it can be changed into a prime (21128454736391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9933784 + ... + 11871687.

It is an arithmetic number, because the mean of its divisors is an integer number (843871766400).

Almost surely, 2^{21128454736392} is an apocalyptic number.

It is an amenable number.

21128454736392 is an abundant number, since it is smaller than the sum of its proper divisors (32879338313208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21128454736392 is a wasteful number, since it uses less digits than its factorization.

21128454736392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21806386 (or 21806382 counting only the distinct ones).

The product of its digits is 17418240, while the sum is 57.

The spelling of 21128454736392 in words is "twenty-one trillion, one hundred twenty-eight billion, four hundred fifty-four million, seven hundred thirty-six thousand, three hundred ninety-two".