21494590 has 16 divisors (see below), whose sum is σ = 41666688. Its totient is φ = 7936416.

The previous prime is 21494573. The next prime is 21494617. The reversal of 21494590 is 9549412.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82542 + ... + 82801.

It is an arithmetic number, because the mean of its divisors is an integer number (2604168).

Almost surely, 2^21494590 is an apocalyptic number.

21494590 is a deficient number, since it is larger than the sum of its proper divisors (20172098).

21494590 is a wasteful number, since it uses less digits than its factorization.

21494590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165363.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 21494590 is about 4636.2258357418. The cubic root of 21494590 is about 278.0415634076.

The spelling of 21494590 in words is "twenty-one million, four hundred ninety-four thousand, five hundred ninety".