21300019451 has 2 divisors, whose sum is σ = 21300019452. Its totient is φ = 21300019450.

The previous prime is 21300019439. The next prime is 21300019453. The reversal of 21300019451 is 15491000312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21300019451 - 2¹⁰ = 21300018427 is a prime.

It is a super-2 number, since 2×21300019451² (a number of 21 digits) contains 22 as substring.

Together with 21300019453, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21300019451.

It is not a weakly prime, because it can be changed into another prime (21300019453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650009725 + 10650009726.

It is an arithmetic number, because the mean of its divisors is an integer number (10650009726).

Almost surely, 2^21300019451 is an apocalyptic number.

21300019451 is a deficient number, since it is larger than the sum of its proper divisors (1).

21300019451 is an equidigital number, since it uses as much as digits as its factorization.

21300019451 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 26.

Adding to 21300019451 its reverse (15491000312), we get a palindrome (36791019763).

The spelling of 21300019451 in words is "twenty-one billion, three hundred million, nineteen thousand, four hundred fifty-one".