21605114 has 16 divisors (see below), whose sum is σ = 34100136. Its totient is φ = 10252800.

The previous prime is 21605107. The next prime is 21605117. The reversal of 21605114 is 41150612.

It can be written as a sum of positive squares in 4 ways, for example, as 11256025 + 10349089 = 3355^2 + 3217^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21605117) 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, 527 + ... + 6594.

Almost surely, 2^21605114 is an apocalyptic number.

21605114 is a deficient number, since it is larger than the sum of its proper divisors (12495022).

21605114 is a wasteful number, since it uses less digits than its factorization.

21605114 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7201.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 21605114 is about 4648.1301616887. The cubic root of 21605114 is about 278.5173070651.

Adding to 21605114 its reverse (41150612), we get a palindrome (62755726).

The spelling of 21605114 in words is "twenty-one million, six hundred five thousand, one hundred fourteen".