99732821 has 2 divisors, whose sum is σ = 99732822. Its totient is φ = 99732820.

The previous prime is 99732811. The next prime is 99732823. The reversal of 99732821 is 12823799.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51638596 + 48094225 = 7186^2 + 6935^2 .

It is an emirp because it is prime and its reverse (12823799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99732821 - 2⁶ = 99732757 is a prime.

Together with 99732823, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99732823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49866410 + 49866411.

It is an arithmetic number, because the mean of its divisors is an integer number (49866411).

Almost surely, 2^99732821 is an apocalyptic number.

It is an amenable number.

99732821 is a deficient number, since it is larger than the sum of its proper divisors (1).

99732821 is an equidigital number, since it uses as much as digits as its factorization.

99732821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 41.

The square root of 99732821 is about 9986.6321149825. The cubic root of 99732821 is about 463.7451363061.

The spelling of 99732821 in words is "ninety-nine million, seven hundred thirty-two thousand, eight hundred twenty-one".