21929356 has 12 divisors (see below), whose sum is σ = 39027240. Its totient is φ = 10778720.

The previous prime is 21929339. The next prime is 21929357. The reversal of 21929356 is 65392912.

It is not an unprimeable number, because it can be changed into a prime (21929357) 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 3 ways as a sum of consecutive naturals, for example, 46225 + ... + 46696.

It is an arithmetic number, because the mean of its divisors is an integer number (3252270).

Almost surely, 2^21929356 is an apocalyptic number.

It is an amenable number.

21929356 is a deficient number, since it is larger than the sum of its proper divisors (17097884).

21929356 is a wasteful number, since it uses less digits than its factorization.

21929356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92984 (or 92982 counting only the distinct ones).

The product of its digits is 29160, while the sum is 37.

The square root of 21929356 is about 4682.8790289735. The cubic root of 21929356 is about 279.9036913673.

The spelling of 21929356 in words is "twenty-one million, nine hundred twenty-nine thousand, three hundred fifty-six".