21364720717124 has 24 divisors (see below), whose sum is σ = 37469818608768. Its totient is φ = 10659081232800.

The previous prime is 21364720717103. The next prime is 21364720717129. The reversal of 21364720717124 is 42171702746312.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21364720717129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 850007 + ... + 6591809.

It is an arithmetic number, because the mean of its divisors is an integer number (1561242442032).

Almost surely, 2^{21364720717124} is an apocalyptic number.

It is an amenable number.

21364720717124 is a deficient number, since it is larger than the sum of its proper divisors (16105097891644).

21364720717124 is a wasteful number, since it uses less digits than its factorization.

21364720717124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5743835 (or 5743833 counting only the distinct ones).

The product of its (nonzero) digits is 790272, while the sum is 47.

The spelling of 21364720717124 in words is "twenty-one trillion, three hundred sixty-four billion, seven hundred twenty million, seven hundred seventeen thousand, one hundred twenty-four".