20741665 has 16 divisors (see below), whose sum is σ = 28575360. Its totient is φ = 14158080.

The previous prime is 20741621. The next prime is 20741713. The reversal of 20741665 is 56614702.

20741665 = 165² + 166² + ... + 405².

It is a happy number.

It is not a de Polignac number, because 20741665 - 2⁷ = 20741537 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7206 + ... + 9664.

It is an arithmetic number, because the mean of its divisors is an integer number (1785960).

Almost surely, 2^20741665 is an apocalyptic number.

It is an amenable number.

20741665 is a deficient number, since it is larger than the sum of its proper divisors (7833695).

20741665 is a wasteful number, since it uses less digits than its factorization.

20741665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2712.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 20741665 is about 4554.3018125724. The cubic root of 20741665 is about 274.7564344772.

The spelling of 20741665 in words is "twenty million, seven hundred forty-one thousand, six hundred sixty-five".