21449290 has 32 divisors (see below), whose sum is σ = 41184000. Its totient is φ = 8019648.

The previous prime is 21449279. The next prime is 21449293. The reversal of 21449290 is 9294412.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21449293) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 14296 + ... + 15724.

It is an arithmetic number, because the mean of its divisors is an integer number (1287000).

Almost surely, 2^21449290 is an apocalyptic number.

21449290 is a deficient number, since it is larger than the sum of its proper divisors (19734710).

21449290 is a wasteful number, since it uses less digits than its factorization.

21449290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1534.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 21449290 is about 4631.3378196802. The cubic root of 21449290 is about 277.8461011787.

The spelling of 21449290 in words is "twenty-one million, four hundred forty-nine thousand, two hundred ninety".