21572113 has 8 divisors (see below), whose sum is σ = 22104576. Its totient is φ = 21044400.

The previous prime is 21572077. The next prime is 21572119. The reversal of 21572113 is 31127512.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21572113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21572119) 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, 9058 + ... + 11188.

It is an arithmetic number, because the mean of its divisors is an integer number (2763072).

Almost surely, 2^21572113 is an apocalyptic number.

It is an amenable number.

21572113 is a deficient number, since it is larger than the sum of its proper divisors (532463).

21572113 is a wasteful number, since it uses less digits than its factorization.

21572113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2375.

The product of its digits is 420, while the sum is 22.

The square root of 21572113 is about 4644.5788829559. The cubic root of 21572113 is about 278.3754265603.

Adding to 21572113 its reverse (31127512), we get a palindrome (52699625).

The spelling of 21572113 in words is "twenty-one million, five hundred seventy-two thousand, one hundred thirteen".