21602161 has 8 divisors (see below), whose sum is σ = 24986304. Its totient is φ = 18292560.

The previous prime is 21602159. The next prime is 21602173. The reversal of 21602161 is 16120612.

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 21602161 - 2¹ = 21602159 is a prime.

It is a super-3 number, since 3×21602161³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21602261) 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, 18010 + ... + 19171.

It is an arithmetic number, because the mean of its divisors is an integer number (3123288).

Almost surely, 2^21602161 is an apocalyptic number.

It is an amenable number.

21602161 is a deficient number, since it is larger than the sum of its proper divisors (3384143).

21602161 is an equidigital number, since it uses as much as digits as its factorization.

21602161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37271.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 21602161 is about 4647.8124962180. The cubic root of 21602161 is about 278.5046171825.

Adding to 21602161 its reverse (16120612), we get a palindrome (37722773).

The spelling of 21602161 in words is "twenty-one million, six hundred two thousand, one hundred sixty-one".