21072376 has 32 divisors (see below), whose sum is σ = 43364160. Its totient is φ = 9539712.

The previous prime is 21072361. The next prime is 21072379. The reversal of 21072376 is 67327012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21072379) 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 7 ways as a sum of consecutive naturals, for example, 3601 + ... + 7423.

It is an arithmetic number, because the mean of its divisors is an integer number (1355130).

Almost surely, 2^21072376 is an apocalyptic number.

21072376 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21072376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21682080).

21072376 is an abundant number, since it is smaller than the sum of its proper divisors (22291784).

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

21072376 is a wasteful number, since it uses less digits than its factorization.

21072376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3895 (or 3891 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 28.

The square root of 21072376 is about 4590.4657715748. The cubic root of 21072376 is about 276.2090064271.

Adding to 21072376 its reverse (67327012), we get a palindrome (88399388).

The spelling of 21072376 in words is "twenty-one million, seventy-two thousand, three hundred seventy-six".