21812619793429 has 2 divisors, whose sum is σ = 21812619793430. Its totient is φ = 21812619793428.

The previous prime is 21812619793423. The next prime is 21812619793649. The reversal of 21812619793429 is 92439791621812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21074434676100 + 738185117329 = 4590690^2 + 859177^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21812619793429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21812619793423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10906309896714 + 10906309896715.

It is an arithmetic number, because the mean of its divisors is an integer number (10906309896715).

Almost surely, 2^{21812619793429} is an apocalyptic number.

It is an amenable number.

21812619793429 is a deficient number, since it is larger than the sum of its proper divisors (1).

21812619793429 is an equidigital number, since it uses as much as digits as its factorization.

21812619793429 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23514624, while the sum is 64.

The spelling of 21812619793429 in words is "twenty-one trillion, eight hundred twelve billion, six hundred nineteen million, seven hundred ninety-three thousand, four hundred twenty-nine".