20206651 has 2 divisors, whose sum is σ = 20206652. Its totient is φ = 20206650.

The previous prime is 20206639. The next prime is 20206657. The reversal of 20206651 is 15660202.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20206651 - 2¹⁹ = 19682363 is a prime.

It is not a weakly prime, because it can be changed into another prime (20206657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10103325 + 10103326.

It is an arithmetic number, because the mean of its divisors is an integer number (10103326).

Almost surely, 2^20206651 is an apocalyptic number.

20206651 is a deficient number, since it is larger than the sum of its proper divisors (1).

20206651 is an equidigital number, since it uses as much as digits as its factorization.

20206651 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 20206651 is about 4495.1808639920. The cubic root of 20206651 is about 272.3734552577.

Adding to 20206651 its reverse (15660202), we get a palindrome (35866853).

The spelling of 20206651 in words is "twenty million, two hundred six thousand, six hundred fifty-one".