21449810 has 16 divisors (see below), whose sum is σ = 39154752. Its totient is φ = 8458800.

The previous prime is 21449807. The next prime is 21449839. The reversal of 21449810 is 1894412.

It is a super-2 number, since 2×21449810² = 920188698072200, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14396 + ... + 15815.

It is an arithmetic number, because the mean of its divisors is an integer number (2447172).

Almost surely, 2^21449810 is an apocalyptic number.

21449810 is a deficient number, since it is larger than the sum of its proper divisors (17704942).

21449810 is a wasteful number, since it uses less digits than its factorization.

21449810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30289.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 21449810 is about 4631.3939586263. The cubic root of 21449810 is about 277.8483464559.

The spelling of 21449810 in words is "twenty-one million, four hundred forty-nine thousand, eight hundred ten".