99227821 has 32 divisors (see below), whose sum is σ = 131546880. Its totient is φ = 72576000.

The previous prime is 99227813. The next prime is 99227833. The reversal of 99227821 is 12872299.

It is not a de Polignac number, because 99227821 - 2³ = 99227813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99227801) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 82021 + ... + 83221.

It is an arithmetic number, because the mean of its divisors is an integer number (4110840).

Almost surely, 2^99227821 is an apocalyptic number.

It is an amenable number.

99227821 is a deficient number, since it is larger than the sum of its proper divisors (32319059).

99227821 is a wasteful number, since it uses less digits than its factorization.

99227821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1285.

The product of its digits is 36288, while the sum is 40.

The square root of 99227821 is about 9961.3162282903. The cubic root of 99227821 is about 462.9610825202.

It can be divided in two parts, 992278 and 21, that added together give a palindrome (992299).

The spelling of 99227821 in words is "ninety-nine million, two hundred twenty-seven thousand, eight hundred twenty-one".