21213244427 has 2 divisors, whose sum is σ = 21213244428. Its totient is φ = 21213244426.

The previous prime is 21213244421. The next prime is 21213244433. The reversal of 21213244427 is 72444231212.

It is a balanced prime because it is at equal distance from previous prime (21213244421) and next prime (21213244433).

It is a cyclic number.

It is not a de Polignac number, because 21213244427 - 2²⁸ = 20944808971 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21213244393 and 21213244402.

It is not a weakly prime, because it can be changed into another prime (21213244421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606622213 + 10606622214.

It is an arithmetic number, because the mean of its divisors is an integer number (10606622214).

Almost surely, 2^21213244427 is an apocalyptic number.

21213244427 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213244427 is an equidigital number, since it uses as much as digits as its factorization.

21213244427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21504, while the sum is 32.

Adding to 21213244427 its reverse (72444231212), we get a palindrome (93657475639).

The spelling of 21213244427 in words is "twenty-one billion, two hundred thirteen million, two hundred forty-four thousand, four hundred twenty-seven".