21109450 has 24 divisors (see below), whose sum is σ = 40533120. Its totient is φ = 8170800.

The previous prime is 21109447. The next prime is 21109457. The reversal of 21109450 is 5490112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21109457) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5260 + ... + 8359.

It is an arithmetic number, because the mean of its divisors is an integer number (1688880).

Almost surely, 2^21109450 is an apocalyptic number.

21109450 is a deficient number, since it is larger than the sum of its proper divisors (19423670).

21109450 is a wasteful number, since it uses less digits than its factorization.

21109450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13662 (or 13657 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 21109450 is about 4594.5021493085. The cubic root of 21109450 is about 276.3708956728.

Adding to 21109450 its reverse (5490112), we get a palindrome (26599562).

The spelling of 21109450 in words is "twenty-one million, one hundred nine thousand, four hundred fifty".