22318821 has 24 divisors (see below), whose sum is σ = 38211264. Its totient is φ = 12752640.

The previous prime is 22318817. The next prime is 22318823. The reversal of 22318821 is 12881322.

It is not a de Polignac number, because 22318821 - 2² = 22318817 is a prime.

It is a super-3 number, since 3×22318821³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22318823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4860 + ... + 8261.

It is an arithmetic number, because the mean of its divisors is an integer number (1592136).

Almost surely, 2^22318821 is an apocalyptic number.

22318821 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

22318821 is a deficient number, since it is larger than the sum of its proper divisors (15892443).

22318821 is an equidigital number, since it uses as much as digits as its factorization.

22318821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13143 (or 13131 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 22318821 is about 4724.2799451345. The cubic root of 22318821 is about 281.5510057359.

It can be divided in two parts, 223 and 18821, that added together give a square (19044 = 138²).

The spelling of 22318821 in words is "twenty-two million, three hundred eighteen thousand, eight hundred twenty-one".