21122064 has 30 divisors (see below), whose sum is σ = 59112846. Its totient is φ = 7040640.

The previous prime is 21122033. The next prime is 21122069. The reversal of 21122064 is 46022112.

It can be written as a sum of positive squares in only one way, i.e., 19184400 + 1937664 = 4380^2 + 1392^2 .

It is a super-2 number, since 2×21122064² = 892283175240192, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21122069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 73197 + ... + 73484.

Almost surely, 2^21122064 is an apocalyptic number.

21122064 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21122064 is an abundant number, since it is smaller than the sum of its proper divisors (37990782).

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

21122064 is a wasteful number, since it uses less digits than its factorization.

21122064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146695 (or 146686 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 21122064 is about 4595.8746719205. The cubic root of 21122064 is about 276.4259333980.

Adding to 21122064 its reverse (46022112), we get a palindrome (67144176).

The spelling of 21122064 in words is "twenty-one million, one hundred twenty-two thousand, sixty-four".