21949256 has 64 divisors (see below), whose sum is σ = 50640000. Its totient is φ = 8890560.

The previous prime is 21949247. The next prime is 21949273. The reversal of 21949256 is 65294912.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 51926 + ... + 52346.

It is an arithmetic number, because the mean of its divisors is an integer number (791250).

Almost surely, 2^21949256 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21949256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25320000).

21949256 is an abundant number, since it is smaller than the sum of its proper divisors (28690744).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21949256 is a wasteful number, since it uses less digits than its factorization.

21949256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 467 (or 449 counting only the distinct ones).

The product of its digits is 38880, while the sum is 38.

The square root of 21949256 is about 4685.0033084300. The cubic root of 21949256 is about 279.9883328472.

The spelling of 21949256 in words is "twenty-one million, nine hundred forty-nine thousand, two hundred fifty-six".