21143287049 has 2 divisors, whose sum is σ = 21143287050. Its totient is φ = 21143287048.

The previous prime is 21143287031. The next prime is 21143287051. The reversal of 21143287049 is 94078234112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13839875449 + 7303411600 = 117643^2 + 85460^2 .

It is a cyclic number.

It is not a de Polignac number, because 21143287049 - 2⁸ = 21143286793 is a prime.

It is a super-2 number, since 2×21143287049² (a number of 21 digits) contains 22 as substring.

Together with 21143287051, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21143286997 and 21143287015.

It is not a weakly prime, because it can be changed into another prime (21143287069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571643524 + 10571643525.

It is an arithmetic number, because the mean of its divisors is an integer number (10571643525).

Almost surely, 2^21143287049 is an apocalyptic number.

It is an amenable number.

21143287049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21143287049 is an equidigital number, since it uses as much as digits as its factorization.

21143287049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 41.

The spelling of 21143287049 in words is "twenty-one billion, one hundred forty-three million, two hundred eighty-seven thousand, forty-nine".