21124231019 has 2 divisors, whose sum is σ = 21124231020. Its totient is φ = 21124231018.

The previous prime is 21124231001. The next prime is 21124231039. The reversal of 21124231019 is 91013242112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21124231019 - 2⁸ = 21124230763 is a prime.

It is a super-2 number, since 2×21124231019² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21124231039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10562115509 + 10562115510.

It is an arithmetic number, because the mean of its divisors is an integer number (10562115510).

Almost surely, 2^21124231019 is an apocalyptic number.

21124231019 is a deficient number, since it is larger than the sum of its proper divisors (1).

21124231019 is an equidigital number, since it uses as much as digits as its factorization.

21124231019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The spelling of 21124231019 in words is "twenty-one billion, one hundred twenty-four million, two hundred thirty-one thousand, nineteen".