20200861 has 8 divisors (see below), whose sum is σ = 20497400. Its totient is φ = 19906560.

The previous prime is 20200847. The next prime is 20200883. The reversal of 20200861 is 16800202.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5904900 + 14295961 = 2430^2 + 3781^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 7-Lehmer number, since φ(20200861) divides (20200861-1)⁷.

It is a cyclic number.

It is not a de Polignac number, because 20200861 - 2¹¹ = 20198813 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 (20200801) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25885 + ... + 26653.

It is an arithmetic number, because the mean of its divisors is an integer number (2562175).

Almost surely, 2^20200861 is an apocalyptic number.

It is an amenable number.

20200861 is a deficient number, since it is larger than the sum of its proper divisors (296539).

20200861 is a wasteful number, since it uses less digits than its factorization.

20200861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1119.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 20200861 is about 4494.5367948210. The cubic root of 20200861 is about 272.3474375378.

The spelling of 20200861 in words is "twenty million, two hundred thousand, eight hundred sixty-one".