21019386 has 16 divisors (see below), whose sum is σ = 42084000. Its totient is φ = 6998928.

The previous prime is 21019381. The next prime is 21019393. The reversal of 21019386 is 68391012.

It is not an unprimeable number, because it can be changed into a prime (21019381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8965 + ... + 11063.

It is an arithmetic number, because the mean of its divisors is an integer number (2630250).

Almost surely, 2^21019386 is an apocalyptic number.

21019386 is an abundant number, since it is smaller than the sum of its proper divisors (21064614).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21019386 is a wasteful number, since it uses less digits than its factorization.

21019386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3773.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 21019386 is about 4584.6903930364. The cubic root of 21019386 is about 275.9772875660.

The spelling of 21019386 in words is "twenty-one million, nineteen thousand, three hundred eighty-six".