21113031243 has 8 divisors (see below), whose sum is σ = 28413799488. Its totient is φ = 13943808584.

The previous prime is 21113031241. The next prime is 21113031253. The reversal of 21113031243 is 34213031112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21113031243 - 2¹ = 21113031241 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21113031241) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 32886021 + ... + 32886662.

It is an arithmetic number, because the mean of its divisors is an integer number (3551724936).

Almost surely, 2^21113031243 is an apocalyptic number.

21113031243 is a deficient number, since it is larger than the sum of its proper divisors (7300768245).

21113031243 is a wasteful number, since it uses less digits than its factorization.

21113031243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65772793.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 21113031243 its reverse (34213031112), we get a palindrome (55326062355).

The spelling of 21113031243 in words is "twenty-one billion, one hundred thirteen million, thirty-one thousand, two hundred forty-three".