20968261 has 8 divisors (see below), whose sum is σ = 21642264. Its totient is φ = 20302080.

The previous prime is 20968237. The next prime is 20968271. The reversal of 20968261 is 16286902.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 664225 + 20304036 = 815^2 + 4506^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20968261 - 2¹¹ = 20966213 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 (20968271) 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, 3751 + ... + 7483.

It is an arithmetic number, because the mean of its divisors is an integer number (2705283).

Almost surely, 2^20968261 is an apocalyptic number.

It is an amenable number.

20968261 is a deficient number, since it is larger than the sum of its proper divisors (674003).

20968261 is a wasteful number, since it uses less digits than its factorization.

20968261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3911.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 20968261 is about 4579.1113766756. Note that the first 3 decimals coincide. The cubic root of 20968261 is about 275.7533547072.

The spelling of 20968261 in words is "twenty million, nine hundred sixty-eight thousand, two hundred sixty-one".