20205313261 has 16 divisors (see below), whose sum is σ = 23486348800. Its totient is φ = 17024836608.

The previous prime is 20205313243. The next prime is 20205313277. The reversal of 20205313261 is 16231350202.

It is a cyclic number.

It is not a de Polignac number, because 20205313261 - 2¹⁵ = 20205280493 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 (20205313201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46861 + ... + 206413.

It is an arithmetic number, because the mean of its divisors is an integer number (1467896800).

Almost surely, 2^20205313261 is an apocalyptic number.

It is an amenable number.

20205313261 is a deficient number, since it is larger than the sum of its proper divisors (3281035539).

20205313261 is a wasteful number, since it uses less digits than its factorization.

20205313261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159868.

The product of its (nonzero) digits is 2160, while the sum is 25.

Adding to 20205313261 its reverse (16231350202), we get a palindrome (36436663463).

The spelling of 20205313261 in words is "twenty billion, two hundred five million, three hundred thirteen thousand, two hundred sixty-one".