21010431243 has 8 divisors (see below), whose sum is σ = 28542472848. Its totient is φ = 13742671904.

The previous prime is 21010431227. The next prime is 21010431251. The reversal of 21010431243 is 34213401012.

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 21010431243 - 2⁴ = 21010431227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21010431643) 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 7 ways as a sum of consecutive naturals, for example, 66070380 + ... + 66070697.

It is an arithmetic number, because the mean of its divisors is an integer number (3567809106).

Almost surely, 2^21010431243 is an apocalyptic number.

21010431243 is a deficient number, since it is larger than the sum of its proper divisors (7532041605).

21010431243 is a wasteful number, since it uses less digits than its factorization.

21010431243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132141133.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21010431243 its reverse (34213401012), we get a palindrome (55223832255).

The spelling of 21010431243 in words is "twenty-one billion, ten million, four hundred thirty-one thousand, two hundred forty-three".