21082379 has 4 divisors (see below), whose sum is σ = 21150480. Its totient is φ = 21014280.

The previous prime is 21082361. The next prime is 21082403. The reversal of 21082379 is 97328012.

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 21082379 - 2⁸ = 21082123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21082309) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33584 + ... + 34205.

It is an arithmetic number, because the mean of its divisors is an integer number (5287620).

Almost surely, 2^21082379 is an apocalyptic number.

21082379 is a deficient number, since it is larger than the sum of its proper divisors (68101).

21082379 is an equidigital number, since it uses as much as digits as its factorization.

21082379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68100.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 21082379 is about 4591.5551831596. Note that the first 3 decimals coincide. The cubic root of 21082379 is about 276.2527047366.

The spelling of 21082379 in words is "twenty-one million, eighty-two thousand, three hundred seventy-nine".