280630861 has 4 divisors (see below), whose sum is σ = 320720992. Its totient is φ = 240540732.

The previous prime is 280630859. The next prime is 280630897. The reversal of 280630861 is 168036082.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 280630861 - 2¹ = 280630859 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 (280630811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20045055 + ... + 20045068.

It is an arithmetic number, because the mean of its divisors is an integer number (80180248).

Almost surely, 2^280630861 is an apocalyptic number.

It is an amenable number.

280630861 is a deficient number, since it is larger than the sum of its proper divisors (40090131).

280630861 is an equidigital number, since it uses as much as digits as its factorization.

280630861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40090130.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 280630861 is about 16752.0405025776. The cubic root of 280630861 is about 654.7042240125.

The spelling of 280630861 in words is "two hundred eighty million, six hundred thirty thousand, eight hundred sixty-one".