21120213122773 has 2 divisors, whose sum is σ = 21120213122774. Its totient is φ = 21120213122772.

The previous prime is 21120213122761. The next prime is 21120213122803. The reversal of 21120213122773 is 37722131202112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21101372266129 + 18840856644 = 4593623^2 + 137262^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21120213122773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21120213132773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560106561386 + 10560106561387.

It is an arithmetic number, because the mean of its divisors is an integer number (10560106561387).

Almost surely, 2^{21120213122773} is an apocalyptic number.

It is an amenable number.

21120213122773 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120213122773 is an equidigital number, since it uses as much as digits as its factorization.

21120213122773 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14112, while the sum is 34.

Adding to 21120213122773 its reverse (37722131202112), we get a palindrome (58842344324885).

The spelling of 21120213122773 in words is "twenty-one trillion, one hundred twenty billion, two hundred thirteen million, one hundred twenty-two thousand, seven hundred seventy-three".