21012193019 has 2 divisors, whose sum is σ = 21012193020. Its totient is φ = 21012193018.

The previous prime is 21012193009. The next prime is 21012193061. The reversal of 21012193019 is 91039121012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21012193019 is a prime.

It is a super-2 number, since 2×21012193019² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21012192982 and 21012193000.

It is not a weakly prime, because it can be changed into another prime (21012193009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506096509 + 10506096510.

It is an arithmetic number, because the mean of its divisors is an integer number (10506096510).

Almost surely, 2^21012193019 is an apocalyptic number.

21012193019 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012193019 is an equidigital number, since it uses as much as digits as its factorization.

21012193019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 29.

The spelling of 21012193019 in words is "twenty-one billion, twelve million, one hundred ninety-three thousand, nineteen".