21813467149 has 2 divisors, whose sum is σ = 21813467150. Its totient is φ = 21813467148.

The previous prime is 21813467147. The next prime is 21813467201. The reversal of 21813467149 is 94176431812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13512435049 + 8301032100 = 116243^2 + 91110^2 .

It is a cyclic number.

It is not a de Polignac number, because 21813467149 - 2¹ = 21813467147 is a prime.

Together with 21813467147, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21813467099 and 21813467108.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21813467147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10906733574 + 10906733575.

It is an arithmetic number, because the mean of its divisors is an integer number (10906733575).

Almost surely, 2^21813467149 is an apocalyptic number.

It is an amenable number.

21813467149 is a deficient number, since it is larger than the sum of its proper divisors (1).

21813467149 is an equidigital number, since it uses as much as digits as its factorization.

21813467149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 46.

The spelling of 21813467149 in words is "twenty-one billion, eight hundred thirteen million, four hundred sixty-seven thousand, one hundred forty-nine".