21983235697 has 2 divisors, whose sum is σ = 21983235698. Its totient is φ = 21983235696.

The previous prime is 21983235671. The next prime is 21983235731. The reversal of 21983235697 is 79653238912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17648856801 + 4334378896 = 132849^2 + 65836^2 .

It is a cyclic number.

It is not a de Polignac number, because 21983235697 - 2¹⁵ = 21983202929 is a prime.

It is not a weakly prime, because it can be changed into another prime (21983235607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10991617848 + 10991617849.

It is an arithmetic number, because the mean of its divisors is an integer number (10991617849).

Almost surely, 2^21983235697 is an apocalyptic number.

It is an amenable number.

21983235697 is a deficient number, since it is larger than the sum of its proper divisors (1).

21983235697 is an equidigital number, since it uses as much as digits as its factorization.

21983235697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 55.

The spelling of 21983235697 in words is "twenty-one billion, nine hundred eighty-three million, two hundred thirty-five thousand, six hundred ninety-seven".