280605631 has 4 divisors (see below), whose sum is σ = 281370592. Its totient is φ = 279840672.

The previous prime is 280605617. The next prime is 280605643. The reversal of 280605631 is 136506082.

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

It is a cyclic number.

It is not a de Polignac number, because 280605631 - 2⁹ = 280605119 is a prime.

It is a super-2 number, since 2×280605631² = 157479040297816322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 280605593 and 280605602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280605601) 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, 381930 + ... + 382663.

It is an arithmetic number, because the mean of its divisors is an integer number (70342648).

Almost surely, 2^280605631 is an apocalyptic number.

280605631 is a deficient number, since it is larger than the sum of its proper divisors (764961).

280605631 is an equidigital number, since it uses as much as digits as its factorization.

280605631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 764960.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 280605631 is about 16751.2874430594. The cubic root of 280605631 is about 654.6846031215.

The spelling of 280605631 in words is "two hundred eighty million, six hundred five thousand, six hundred thirty-one".