21242822 has 4 divisors (see below), whose sum is σ = 31864236. Its totient is φ = 10621410.

The previous prime is 21242821. The next prime is 21242827. The reversal of 21242822 is 22824212.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5310704 + ... + 5310707.

It is an arithmetic number, because the mean of its divisors is an integer number (7966059).

Almost surely, 2^21242822 is an apocalyptic number.

21242822 is a deficient number, since it is larger than the sum of its proper divisors (10621414).

21242822 is a wasteful number, since it uses less digits than its factorization.

21242822 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10621413.

The product of its digits is 1024, while the sum is 23.

The square root of 21242822 is about 4608.9935994748. The cubic root of 21242822 is about 276.9517221357.

It can be divided in two parts, 212 and 42822, that added together give a palindrome (43034).

The spelling of 21242822 in words is "twenty-one million, two hundred forty-two thousand, eight hundred twenty-two".