20299261 has 4 divisors (see below), whose sum is σ = 20309500. Its totient is φ = 20289024.

The previous prime is 20299259. The next prime is 20299267. The reversal of 20299261 is 16299202.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 16299202 = 2 ⋅8149601.

It can be written as a sum of positive squares in 2 ways, for example, as 7873636 + 12425625 = 2806^2 + 3525^2 .

It is a cyclic number.

It is not a de Polignac number, because 20299261 - 2¹ = 20299259 is a prime.

It is a super-2 number, since 2×20299261² = 824119994292242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20299267) 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, 1086 + ... + 6463.

It is an arithmetic number, because the mean of its divisors is an integer number (5077375).

Almost surely, 2^20299261 is an apocalyptic number.

It is an amenable number.

20299261 is a deficient number, since it is larger than the sum of its proper divisors (10239).

20299261 is an equidigital number, since it uses as much as digits as its factorization.

20299261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10238.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 20299261 is about 4505.4701197544. The cubic root of 20299261 is about 272.7889301371.

The spelling of 20299261 in words is "twenty million, two hundred ninety-nine thousand, two hundred sixty-one".