20860261 has 4 divisors (see below), whose sum is σ = 21146092. Its totient is φ = 20574432.

The previous prime is 20860253. The next prime is 20860277. The reversal of 20860261 is 16206802.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16206802 = 2 ⋅8103401.

It can be written as a sum of positive squares in 2 ways, for example, as 8122500 + 12737761 = 2850^2 + 3569^2 .

It is a cyclic number.

It is not a de Polignac number, because 20860261 - 2³ = 20860253 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 (20860201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 142806 + ... + 142951.

It is an arithmetic number, because the mean of its divisors is an integer number (5286523).

Almost surely, 2^20860261 is an apocalyptic number.

It is an amenable number.

20860261 is a deficient number, since it is larger than the sum of its proper divisors (285831).

20860261 is an equidigital number, since it uses as much as digits as its factorization.

20860261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285830.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 20860261 is about 4567.3034714151. The cubic root of 20860261 is about 275.2791039628.

The spelling of 20860261 in words is "twenty million, eight hundred sixty thousand, two hundred sixty-one".