21147301849 has 2 divisors, whose sum is σ = 21147301850. Its totient is φ = 21147301848.

The previous prime is 21147301843. The next prime is 21147301867. The reversal of 21147301849 is 94810374112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21114124249 + 33177600 = 145307^2 + 5760^2 .

It is a cyclic number.

It is not a de Polignac number, because 21147301849 - 2⁵ = 21147301817 is a prime.

It is not a weakly prime, because it can be changed into another prime (21147301843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10573650924 + 10573650925.

It is an arithmetic number, because the mean of its divisors is an integer number (10573650925).

Almost surely, 2^21147301849 is an apocalyptic number.

It is an amenable number.

21147301849 is a deficient number, since it is larger than the sum of its proper divisors (1).

21147301849 is an equidigital number, since it uses as much as digits as its factorization.

21147301849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 40.

The spelling of 21147301849 in words is "twenty-one billion, one hundred forty-seven million, three hundred one thousand, eight hundred forty-nine".