21197592 has 64 divisors (see below), whose sum is σ = 63420000. Its totient is φ = 6521472.

The previous prime is 21197591. The next prime is 21197593. The reversal of 21197592 is 29579112.

It is an interprime number because it is at equal distance from previous prime (21197591) and next prime (21197593).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21197591) 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 15 ways as a sum of consecutive naturals, for example, 967 + ... + 6582.

Almost surely, 2^21197592 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21197592, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31710000).

21197592 is an abundant number, since it is smaller than the sum of its proper divisors (42222408).

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

21197592 is a wasteful number, since it uses less digits than its factorization.

21197592 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7577 (or 7567 counting only the distinct ones).

The product of its digits is 11340, while the sum is 36.

The square root of 21197592 is about 4604.0842737726. The cubic root of 21197592 is about 276.7550215377.

The spelling of 21197592 in words is "twenty-one million, one hundred ninety-seven thousand, five hundred ninety-two".