21623822 has 16 divisors (see below), whose sum is σ = 35752752. Its totient is φ = 9726720.

The previous prime is 21623809. The next prime is 21623827. The reversal of 21623822 is 22832612.

It is a super-3 number, since 3×21623822³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21623791 and 21623800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21623827) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2933 + ... + 7200.

It is an arithmetic number, because the mean of its divisors is an integer number (2234547).

Almost surely, 2^21623822 is an apocalyptic number.

21623822 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21623822 is a deficient number, since it is larger than the sum of its proper divisors (14128930).

21623822 is a wasteful number, since it uses less digits than its factorization.

21623822 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10243.

The product of its digits is 2304, while the sum is 26.

The square root of 21623822 is about 4650.1421483649. The cubic root of 21623822 is about 278.5976738179.

The spelling of 21623822 in words is "twenty-one million, six hundred twenty-three thousand, eight hundred twenty-two".