21919370 has 16 divisors (see below), whose sum is σ = 43041888. Its totient is φ = 7970640.

The previous prime is 21919363. The next prime is 21919393. The reversal of 21919370 is 7391912.

It is a happy number.

It is an unprimeable number.

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, 99524 + ... + 99743.

It is an arithmetic number, because the mean of its divisors is an integer number (2690118).

Almost surely, 2^21919370 is an apocalyptic number.

21919370 is a deficient number, since it is larger than the sum of its proper divisors (21122518).

21919370 is a wasteful number, since it uses less digits than its factorization.

21919370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199285.

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 21919370 is about 4681.8126831389. The cubic root of 21919370 is about 279.8611982113.

The spelling of 21919370 in words is "twenty-one million, nine hundred nineteen thousand, three hundred seventy".