21201115 has 8 divisors (see below), whose sum is σ = 27398448. Its totient is φ = 15656160.

The previous prime is 21201109. The next prime is 21201121. The reversal of 21201115 is 51110212.

It is an interprime number because it is at equal distance from previous prime (21201109) and next prime (21201121).

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

It is not a de Polignac number, because 21201115 - 2⁵ = 21201083 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201095 and 21201104.

It is an unprimeable number.

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, 163021 + ... + 163150.

It is an arithmetic number, because the mean of its divisors is an integer number (3424806).

Almost surely, 2^21201115 is an apocalyptic number.

21201115 is a deficient number, since it is larger than the sum of its proper divisors (6197333).

21201115 is a wasteful number, since it uses less digits than its factorization.

21201115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326189.

The product of its (nonzero) digits is 20, while the sum is 13.

The square root of 21201115 is about 4604.4668529592. The cubic root of 21201115 is about 276.7703527434.

Adding to 21201115 its reverse (51110212), we get a palindrome (72311327).

It can be divided in two parts, 21201 and 115, that added together give a square (21316 = 146²).

The spelling of 21201115 in words is "twenty-one million, two hundred one thousand, one hundred fifteen".