21202671 has 8 divisors (see below), whose sum is σ = 32308864. Its totient is φ = 12115800.

The previous prime is 21202669. The next prime is 21202681. The reversal of 21202671 is 17620212.

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

It is not a de Polignac number, because 21202671 - 2¹ = 21202669 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 1009651 = 21202671 / (2 + 1 + 2 + 0 + 2 + 6 + 7 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 504805 + ... + 504846.

It is an arithmetic number, because the mean of its divisors is an integer number (4038608).

Almost surely, 2^21202671 is an apocalyptic number.

21202671 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21202671 is a deficient number, since it is larger than the sum of its proper divisors (11106193).

21202671 is a wasteful number, since it uses less digits than its factorization.

21202671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1009661.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 21202671 is about 4604.6358162183. The cubic root of 21202671 is about 276.7771235215. Note that the first 3 decimals are identical.

Adding to 21202671 its reverse (17620212), we get a palindrome (38822883).

The spelling of 21202671 in words is "twenty-one million, two hundred two thousand, six hundred seventy-one".