21140916 has 24 divisors (see below), whose sum is σ = 49820064. Its totient is φ = 6976800.

The previous prime is 21140909. The next prime is 21140921. The reversal of 21140916 is 61904112.

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 7 ways as a sum of consecutive naturals, for example, 7510 + ... + 9933.

It is an arithmetic number, because the mean of its divisors is an integer number (2075836).

Almost surely, 2^21140916 is an apocalyptic number.

It is an amenable number.

21140916 is an abundant number, since it is smaller than the sum of its proper divisors (28679148).

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

21140916 is a wasteful number, since it uses less digits than its factorization.

21140916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17551 (or 17549 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 21140916 is about 4597.9251842543. The cubic root of 21140916 is about 276.5081480921.

The spelling of 21140916 in words is "twenty-one million, one hundred forty thousand, nine hundred sixteen".