21953064 has 64 divisors (see below), whose sum is σ = 63216000. Its totient is φ = 6223104.

The previous prime is 21953051. The next prime is 21953143. The reversal of 21953064 is 46035912.

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, 24594 + ... + 25470.

It is an arithmetic number, because the mean of its divisors is an integer number (987750).

Almost surely, 2^21953064 is an apocalyptic number.

21953064 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21953064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31608000).

21953064 is an abundant number, since it is smaller than the sum of its proper divisors (41262936).

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

21953064 is a wasteful number, since it uses less digits than its factorization.

21953064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1042 (or 1038 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 21953064 is about 4685.4096939329. The cubic root of 21953064 is about 280.0045237364.

Adding to 21953064 its reverse (46035912), we get a palindrome (67988976).

The spelling of 21953064 in words is "twenty-one million, nine hundred fifty-three thousand, sixty-four".