21953930 has 16 divisors (see below), whose sum is σ = 41597280. Its totient is φ = 8319312.

The previous prime is 21953923. The next prime is 21953963. The reversal of 21953930 is 3935912.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57584 + ... + 57963.

It is an arithmetic number, because the mean of its divisors is an integer number (2599830).

Almost surely, 2^21953930 is an apocalyptic number.

21953930 is a deficient number, since it is larger than the sum of its proper divisors (19643350).

21953930 is a wasteful number, since it uses less digits than its factorization.

21953930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115573.

The product of its (nonzero) digits is 7290, while the sum is 32.

The square root of 21953930 is about 4685.5021075654. The cubic root of 21953930 is about 280.0082055418.

The spelling of 21953930 in words is "twenty-one million, nine hundred fifty-three thousand, nine hundred thirty".