20297261 has 4 divisors (see below), whose sum is σ = 20381724. Its totient is φ = 20212800.

The previous prime is 20297243. The next prime is 20297273. The reversal of 20297261 is 16279202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18541636 + 1755625 = 4306^2 + 1325^2 .

It is a cyclic number.

It is not a de Polignac number, because 20297261 - 2¹⁴ = 20280877 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20297861) 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, 41870 + ... + 42351.

It is an arithmetic number, because the mean of its divisors is an integer number (5095431).

Almost surely, 2^20297261 is an apocalyptic number.

It is an amenable number.

20297261 is a deficient number, since it is larger than the sum of its proper divisors (84463).

20297261 is an equidigital number, since it uses as much as digits as its factorization.

20297261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84462.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 20297261 is about 4505.2481618663. The cubic root of 20297261 is about 272.7799709311.

The spelling of 20297261 in words is "twenty million, two hundred ninety-seven thousand, two hundred sixty-one".