21751027 has 2 divisors, whose sum is σ = 21751028. Its totient is φ = 21751026.

The previous prime is 21751021. The next prime is 21751039. The reversal of 21751027 is 72015712.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21751027 - 2³ = 21751019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21750992 and 21751010.

It is not a weakly prime, because it can be changed into another prime (21751021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10875513 + 10875514.

It is an arithmetic number, because the mean of its divisors is an integer number (10875514).

Almost surely, 2^21751027 is an apocalyptic number.

21751027 is a deficient number, since it is larger than the sum of its proper divisors (1).

21751027 is an equidigital number, since it uses as much as digits as its factorization.

21751027 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 980, while the sum is 25.

The square root of 21751027 is about 4663.7996312020. The cubic root of 21751027 is about 279.1429020042.

Adding to 21751027 its reverse (72015712), we get a palindrome (93766739).

The spelling of 21751027 in words is "twenty-one million, seven hundred fifty-one thousand, twenty-seven".