21215124383 has 2 divisors, whose sum is σ = 21215124384. Its totient is φ = 21215124382.

The previous prime is 21215124379. The next prime is 21215124407. The reversal of 21215124383 is 38342151212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21215124383 - 2² = 21215124379 is a prime.

It is a super-2 number, since 2×21215124383² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21215124323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10607562191 + 10607562192.

It is an arithmetic number, because the mean of its divisors is an integer number (10607562192).

Almost surely, 2^21215124383 is an apocalyptic number.

21215124383 is a deficient number, since it is larger than the sum of its proper divisors (1).

21215124383 is an equidigital number, since it uses as much as digits as its factorization.

21215124383 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 32.

Adding to 21215124383 its reverse (38342151212), we get a palindrome (59557275595).

The spelling of 21215124383 in words is "twenty-one billion, two hundred fifteen million, one hundred twenty-four thousand, three hundred eighty-three".