21797316 has 24 divisors (see below), whose sum is σ = 56511840. Its totient is φ = 7265736.

The previous prime is 21797297. The next prime is 21797327. The reversal of 21797316 is 61379712.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 100806 + ... + 101021.

It is an arithmetic number, because the mean of its divisors is an integer number (2354660).

Almost surely, 2^21797316 is an apocalyptic number.

It is an amenable number.

21797316 is an abundant number, since it is smaller than the sum of its proper divisors (34714524).

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

21797316 is a wasteful number, since it uses less digits than its factorization.

21797316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201840 (or 201832 counting only the distinct ones).

The product of its digits is 15876, while the sum is 36.

The square root of 21797316 is about 4668.7595783034. The cubic root of 21797316 is about 279.3407791065.

The spelling of 21797316 in words is "twenty-one million, seven hundred ninety-seven thousand, three hundred sixteen".