21996416 has 32 divisors (see below), whose sum is σ = 47195400. Its totient is φ = 10151424.

The previous prime is 21996409. The next prime is 21996427. The reversal of 21996416 is 61469912.

It is a tau number, because it is divible by the number of its divisors (32).

It is a self number, because there is not a number n which added to its sum of digits gives 21996416.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 4946 + ... + 8273.

Almost surely, 2^21996416 is an apocalyptic number.

21996416 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21996416 is an abundant number, since it is smaller than the sum of its proper divisors (25198984).

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

21996416 is a wasteful number, since it uses less digits than its factorization.

21996416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13246 (or 13234 counting only the distinct ones).

The product of its digits is 23328, while the sum is 38.

The square root of 21996416 is about 4690.0336885784. The cubic root of 21996416 is about 280.1887163165.

The spelling of 21996416 in words is "twenty-one million, nine hundred ninety-six thousand, four hundred sixteen".