21896371 has 4 divisors (see below), whose sum is σ = 25024432. Its totient is φ = 18768312.

The previous prime is 21896339. The next prime is 21896387. The reversal of 21896371 is 17369812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21896371 - 2⁵ = 21896339 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21896371.

It is not an unprimeable number, because it can be changed into a prime (21896071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1564020 + ... + 1564033.

It is an arithmetic number, because the mean of its divisors is an integer number (6256108).

Almost surely, 2^21896371 is an apocalyptic number.

21896371 is a deficient number, since it is larger than the sum of its proper divisors (3128061).

21896371 is an equidigital number, since it uses as much as digits as its factorization.

21896371 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3128060.

The product of its digits is 18144, while the sum is 37.

The square root of 21896371 is about 4679.3558317358. The cubic root of 21896371 is about 279.7632820729.

The spelling of 21896371 in words is "twenty-one million, eight hundred ninety-six thousand, three hundred seventy-one".