20910061 has 4 divisors (see below), whose sum is σ = 20943324. Its totient is φ = 20876800.

The previous prime is 20910031. The next prime is 20910067. The reversal of 20910061 is 16001902.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16048036 + 4862025 = 4006^2 + 2205^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20910061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20910067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15670 + ... + 16951.

It is an arithmetic number, because the mean of its divisors is an integer number (5235831).

Almost surely, 2^20910061 is an apocalyptic number.

It is an amenable number.

20910061 is a deficient number, since it is larger than the sum of its proper divisors (33263).

20910061 is an equidigital number, since it uses as much as digits as its factorization.

20910061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33262.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 20910061 is about 4572.7520160184. The cubic root of 20910061 is about 275.4979891224.

Adding to 20910061 its reverse (16001902), we get a palindrome (36911963).

The spelling of 20910061 in words is "twenty million, nine hundred ten thousand, sixty-one".