88211821 has 2 divisors, whose sum is σ = 88211822. Its totient is φ = 88211820.

The previous prime is 88211807. The next prime is 88211857. The reversal of 88211821 is 12811288.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74149321 + 14062500 = 8611^2 + 3750^2 .

It is a cyclic number.

It is not a de Polignac number, because 88211821 - 2⁹ = 88211309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (88217821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 44105910 + 44105911.

It is an arithmetic number, because the mean of its divisors is an integer number (44105911).

Almost surely, 2^88211821 is an apocalyptic number.

It is an amenable number.

88211821 is a deficient number, since it is larger than the sum of its proper divisors (1).

88211821 is an equidigital number, since it uses as much as digits as its factorization.

88211821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2048, while the sum is 31.

The square root of 88211821 is about 9392.1148310697. The cubic root of 88211821 is about 445.1526152462.

The spelling of 88211821 in words is "eighty-eight million, two hundred eleven thousand, eight hundred twenty-one".