21974855 has 32 divisors (see below), whose sum is σ = 31518720. Its totient is φ = 14394240.

The previous prime is 21974851. The next prime is 21974881. The reversal of 21974855 is 55847912.

It is not a de Polignac number, because 21974855 - 2² = 21974851 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21974851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 91826 + ... + 92064.

It is an arithmetic number, because the mean of its divisors is an integer number (984960).

Almost surely, 2^21974855 is an apocalyptic number.

21974855 is a deficient number, since it is larger than the sum of its proper divisors (9543865).

21974855 is a wasteful number, since it uses less digits than its factorization.

21974855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 359.

The product of its digits is 100800, while the sum is 41.

The square root of 21974855 is about 4687.7345274663. The cubic root of 21974855 is about 280.0971389153.

The spelling of 21974855 in words is "twenty-one million, nine hundred seventy-four thousand, eight hundred fifty-five".