21795874017377 has 2 divisors, whose sum is σ = 21795874017378. Its totient is φ = 21795874017376.

The previous prime is 21795874017331. The next prime is 21795874017383. The reversal of 21795874017377 is 77371047859712.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19236373193041 + 2559500824336 = 4385929^2 + 1599844^2 .

It is a cyclic number.

It is not a de Polignac number, because 21795874017377 - 2¹⁰ = 21795874016353 is a prime.

It is not a weakly prime, because it can be changed into another prime (21795874017077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10897937008688 + 10897937008689.

It is an arithmetic number, because the mean of its divisors is an integer number (10897937008689).

Almost surely, 2^{21795874017377} is an apocalyptic number.

It is an amenable number.

21795874017377 is a deficient number, since it is larger than the sum of its proper divisors (1).

21795874017377 is an equidigital number, since it uses as much as digits as its factorization.

21795874017377 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145212480, while the sum is 68.

The spelling of 21795874017377 in words is "twenty-one trillion, seven hundred ninety-five billion, eight hundred seventy-four million, seventeen thousand, three hundred seventy-seven".