21161055701 has 2 divisors, whose sum is σ = 21161055702. Its totient is φ = 21161055700.

The previous prime is 21161055697. The next prime is 21161055739. The reversal of 21161055701 is 10755016112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20981522500 + 179533201 = 144850^2 + 13399^2 .

It is a cyclic number.

It is not a de Polignac number, because 21161055701 - 2² = 21161055697 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21161052701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10580527850 + 10580527851.

It is an arithmetic number, because the mean of its divisors is an integer number (10580527851).

Almost surely, 2^21161055701 is an apocalyptic number.

It is an amenable number.

21161055701 is a deficient number, since it is larger than the sum of its proper divisors (1).

21161055701 is an equidigital number, since it uses as much as digits as its factorization.

21161055701 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2100, while the sum is 29.

The spelling of 21161055701 in words is "twenty-one billion, one hundred sixty-one million, fifty-five thousand, seven hundred one".