21611464 has 64 divisors (see below), whose sum is σ = 48844800. Its totient is φ = 8769600.

The previous prime is 21611461. The next prime is 21611519. The reversal of 21611464 is 46411612.

It is not an unprimeable number, because it can be changed into a prime (21611461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 102319 + ... + 102529.

It is an arithmetic number, because the mean of its divisors is an integer number (763200).

Almost surely, 2^21611464 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 21611464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24422400).

21611464 is an abundant number, since it is smaller than the sum of its proper divisors (27233336).

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

21611464 is a wasteful number, since it uses less digits than its factorization.

21611464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314 (or 310 counting only the distinct ones).

The product of its digits is 1152, while the sum is 25.

The square root of 21611464 is about 4648.8131818777. The cubic root of 21611464 is about 278.5445909088.

The spelling of 21611464 in words is "twenty-one million, six hundred eleven thousand, four hundred sixty-four".