21133544251 has 2 divisors, whose sum is σ = 21133544252. Its totient is φ = 21133544250.

The previous prime is 21133544233. The next prime is 21133544269. The reversal of 21133544251 is 15244533112.

It is a balanced prime because it is at equal distance from previous prime (21133544233) and next prime (21133544269).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21133544251 is a prime.

It is not a weakly prime, because it can be changed into another prime (21133544291) 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 as a sum of consecutive naturals, namely, 10566772125 + 10566772126.

It is an arithmetic number, because the mean of its divisors is an integer number (10566772126).

Almost surely, 2^21133544251 is an apocalyptic number.

21133544251 is a deficient number, since it is larger than the sum of its proper divisors (1).

21133544251 is an equidigital number, since it uses as much as digits as its factorization.

21133544251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14400, while the sum is 31.

The spelling of 21133544251 in words is "twenty-one billion, one hundred thirty-three million, five hundred forty-four thousand, two hundred fifty-one".