21197862 has 112 divisors (see below), whose sum is σ = 57080832. Its totient is φ = 5773680.

The previous prime is 21197857. The next prime is 21197867. The reversal of 21197862 is 26879112.

It is an interprime number because it is at equal distance from previous prime (21197857) and next prime (21197867).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21197867) 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 55 ways as a sum of consecutive naturals, for example, 316353 + ... + 316419.

Almost surely, 2^21197862 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21197862, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28540416).

21197862 is an abundant number, since it is smaller than the sum of its proper divisors (35882970).

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

21197862 is an equidigital number, since it uses as much as digits as its factorization.

21197862 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125 (or 110 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 21197862 is about 4604.1135954709. The cubic root of 21197862 is about 276.7561965696.

The spelling of 21197862 in words is "twenty-one million, one hundred ninety-seven thousand, eight hundred sixty-two".