1280561258 has 4 divisors (see below), whose sum is σ = 1920841890. Its totient is φ = 640280628.

The previous prime is 1280561239. The next prime is 1280561273. The reversal of 1280561258 is 8521650821.

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

It can be written as a sum of positive squares in only one way, i.e., 967023409 + 313537849 = 31097^2 + 17707^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320140313 + ... + 320140316.

Almost surely, 2^1280561258 is an apocalyptic number.

1280561258 is a deficient number, since it is larger than the sum of its proper divisors (640280632).

1280561258 is an equidigital number, since it uses as much as digits as its factorization.

1280561258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640280631.

The product of its (nonzero) digits is 38400, while the sum is 38.

The square root of 1280561258 is about 35784.9305993459. The cubic root of 1280561258 is about 1085.9257201778.

The spelling of 1280561258 in words is "one billion, two hundred eighty million, five hundred sixty-one thousand, two hundred fifty-eight".