20662257 has 32 divisors (see below), whose sum is σ = 35850240. Its totient is φ = 10264320.

The previous prime is 20662247. The next prime is 20662273. The reversal of 20662257 is 75226602.

It is not a de Polignac number, because 20662257 - 2⁴ = 20662241 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20662247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3369 + ... + 7257.

It is an arithmetic number, because the mean of its divisors is an integer number (1120320).

Almost surely, 2^20662257 is an apocalyptic number.

It is an amenable number.

20662257 is a deficient number, since it is larger than the sum of its proper divisors (15187983).

20662257 is a wasteful number, since it uses less digits than its factorization.

20662257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3933.

The product of its (nonzero) digits is 10080, while the sum is 30.

The square root of 20662257 is about 4545.5755411169. The cubic root of 20662257 is about 274.4053575341.

Adding to 20662257 its reverse (75226602), we get a palindrome (95888859).

The spelling of 20662257 in words is "twenty million, six hundred sixty-two thousand, two hundred fifty-seven".