21755146 has 16 divisors (see below), whose sum is σ = 37373760. Its totient is φ = 9303840.

The previous prime is 21755143. The next prime is 21755159. The reversal of 21755146 is 64155712.

It is not an unprimeable number, because it can be changed into a prime (21755141) 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, 6601 + ... + 9331.

It is an arithmetic number, because the mean of its divisors is an integer number (2335860).

Almost surely, 2^21755146 is an apocalyptic number.

21755146 is a deficient number, since it is larger than the sum of its proper divisors (15618614).

21755146 is a wasteful number, since it uses less digits than its factorization.

21755146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3309.

The product of its digits is 8400, while the sum is 31.

The square root of 21755146 is about 4664.2412030254. The cubic root of 21755146 is about 279.1605213568.

The spelling of 21755146 in words is "twenty-one million, seven hundred fifty-five thousand, one hundred forty-six".