821232101 has 2 divisors, whose sum is σ = 821232102. Its totient is φ = 821232100.

The previous prime is 821232059. The next prime is 821232119. The reversal of 821232101 is 101232128.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 808264900 + 12967201 = 28430^2 + 3601^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-821232101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (821832101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410616050 + 410616051.

It is an arithmetic number, because the mean of its divisors is an integer number (410616051).

Almost surely, 2^821232101 is an apocalyptic number.

It is an amenable number.

821232101 is a deficient number, since it is larger than the sum of its proper divisors (1).

821232101 is an equidigital number, since it uses as much as digits as its factorization.

821232101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 821232101 is about 28657.1474679529. The cubic root of 821232101 is about 936.4587221899.

Adding to 821232101 its reverse (101232128), we get a palindrome (922464229).

The spelling of 821232101 in words is "eight hundred twenty-one million, two hundred thirty-two thousand, one hundred one".