21154252727 has 2 divisors, whose sum is σ = 21154252728. Its totient is φ = 21154252726.

The previous prime is 21154252687. The next prime is 21154252759. The reversal of 21154252727 is 72725245112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21154252727 - 2¹⁴ = 21154236343 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21154252127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10577126363 + 10577126364.

It is an arithmetic number, because the mean of its divisors is an integer number (10577126364).

Almost surely, 2^21154252727 is an apocalyptic number.

21154252727 is a deficient number, since it is larger than the sum of its proper divisors (1).

21154252727 is an equidigital number, since it uses as much as digits as its factorization.

21154252727 is an evil number, because the sum of its binary digits is even.

The product of its digits is 78400, while the sum is 38.

Adding to 21154252727 its reverse (72725245112), we get a palindrome (93879497839).

The spelling of 21154252727 in words is "twenty-one billion, one hundred fifty-four million, two hundred fifty-two thousand, seven hundred twenty-seven".