21071351 has 8 divisors (see below), whose sum is σ = 24858624. Its totient is φ = 17478360.

The previous prime is 21071339. The next prime is 21071363. The reversal of 21071351 is 15317012.

It is an interprime number because it is at equal distance from previous prime (21071339) and next prime (21071363).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21071351 - 2⁶ = 21071287 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21071321) 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 7 ways as a sum of consecutive naturals, for example, 48335 + ... + 48768.

It is an arithmetic number, because the mean of its divisors is an integer number (3107328).

Almost surely, 2^21071351 is an apocalyptic number.

21071351 is a deficient number, since it is larger than the sum of its proper divisors (3787273).

21071351 is an equidigital number, since it uses as much as digits as its factorization.

21071351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97141.

The product of its (nonzero) digits is 210, while the sum is 20.

The square root of 21071351 is about 4590.3541257729. The cubic root of 21071351 is about 276.2045279127.

Adding to 21071351 its reverse (15317012), we get a palindrome (36388363).

The spelling of 21071351 in words is "twenty-one million, seventy-one thousand, three hundred fifty-one".