21701331409 has 2 divisors, whose sum is σ = 21701331410. Its totient is φ = 21701331408.

The previous prime is 21701331389. The next prime is 21701331413. The reversal of 21701331409 is 90413310712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21567859600 + 133471809 = 146860^2 + 11553^2 .

It is a cyclic number.

It is not a de Polignac number, because 21701331409 - 2¹¹ = 21701329361 is a prime.

It is not a weakly prime, because it can be changed into another prime (21701338409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10850665704 + 10850665705.

It is an arithmetic number, because the mean of its divisors is an integer number (10850665705).

Almost surely, 2^21701331409 is an apocalyptic number.

It is an amenable number.

21701331409 is a deficient number, since it is larger than the sum of its proper divisors (1).

21701331409 is an equidigital number, since it uses as much as digits as its factorization.

21701331409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 31.

The spelling of 21701331409 in words is "twenty-one billion, seven hundred one million, three hundred thirty-one thousand, four hundred nine".