20988061 has 2 divisors, whose sum is σ = 20988062. Its totient is φ = 20988060.

The previous prime is 20988041. The next prime is 20988089. The reversal of 20988061 is 16088902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20985561 + 2500 = 4581^2 + 50^2 .

It is a cyclic number.

It is not a de Polignac number, because 20988061 - 2¹⁵ = 20955293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20988031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10494030 + 10494031.

It is an arithmetic number, because the mean of its divisors is an integer number (10494031).

Almost surely, 2^20988061 is an apocalyptic number.

It is an amenable number.

20988061 is a deficient number, since it is larger than the sum of its proper divisors (1).

20988061 is an equidigital number, since it uses as much as digits as its factorization.

20988061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 20988061 is about 4581.2728580603. The cubic root of 20988061 is about 275.8401239240.

The spelling of 20988061 in words is "twenty million, nine hundred eighty-eight thousand, sixty-one".