21927955 has 16 divisors (see below), whose sum is σ = 30642624. Its totient is φ = 14751360.

The previous prime is 21927953. The next prime is 21928001. The reversal of 21927955 is 55972912.

It is not a de Polignac number, because 21927955 - 2¹ = 21927953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21927953) 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, 4056 + ... + 7765.

It is an arithmetic number, because the mean of its divisors is an integer number (1915164).

Almost surely, 2^21927955 is an apocalyptic number.

21927955 is a deficient number, since it is larger than the sum of its proper divisors (8714669).

21927955 is a wasteful number, since it uses less digits than its factorization.

21927955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11886.

The product of its digits is 56700, while the sum is 40.

The square root of 21927955 is about 4682.7294391199. The cubic root of 21927955 is about 279.8977305079.

The spelling of 21927955 in words is "twenty-one million, nine hundred twenty-seven thousand, nine hundred fifty-five".