20168261 has 4 divisors (see below), whose sum is σ = 20224800. Its totient is φ = 20111724.

The previous prime is 20168257. The next prime is 20168279. The reversal of 20168261 is 16286102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20168261 - 2² = 20168257 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20168261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20168231) 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, 27731 + ... + 28448.

It is an arithmetic number, because the mean of its divisors is an integer number (5056200).

Almost surely, 2^20168261 is an apocalyptic number.

It is an amenable number.

20168261 is a deficient number, since it is larger than the sum of its proper divisors (56539).

20168261 is an equidigital number, since it uses as much as digits as its factorization.

20168261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56538.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 20168261 is about 4490.9087053736. The cubic root of 20168261 is about 272.2008545648.

The spelling of 20168261 in words is "twenty million, one hundred sixty-eight thousand, two hundred sixty-one".