20280261 has 8 divisors (see below), whose sum is σ = 27065664. Its totient is φ = 13507520.

The previous prime is 20280259. The next prime is 20280287. The reversal of 20280261 is 16208202.

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 20280261 - 2¹ = 20280259 is a prime.

It is a super-2 number, since 2×20280261² = 822577972456242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20280061) 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, 1600 + ... + 6566.

It is an arithmetic number, because the mean of its divisors is an integer number (3383208).

Almost surely, 2^20280261 is an apocalyptic number.

It is an amenable number.

20280261 is a deficient number, since it is larger than the sum of its proper divisors (6785403).

20280261 is a wasteful number, since it uses less digits than its factorization.

20280261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6331.

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 20280261 is about 4503.3610781282. The cubic root of 20280261 is about 272.7037939081.

Adding to 20280261 its reverse (16208202), we get a palindrome (36488463).

The spelling of 20280261 in words is "twenty million, two hundred eighty thousand, two hundred sixty-one".