1281530681 has 8 divisors (see below), whose sum is σ = 1304334240. Its totient is φ = 1258763328.

The previous prime is 1281530671. The next prime is 1281530683. The reversal of 1281530681 is 1860351821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1281530681 is a prime.

It is a super-2 number, since 2×1281530681² = 3284641772688647522, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1281530683) 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, 68150 + ... + 84896.

It is an arithmetic number, because the mean of its divisors is an integer number (163041780).

Almost surely, 2^1281530681 is an apocalyptic number.

It is an amenable number.

1281530681 is a deficient number, since it is larger than the sum of its proper divisors (22803559).

1281530681 is a wasteful number, since it uses less digits than its factorization.

1281530681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18103.

The product of its (nonzero) digits is 11520, while the sum is 35.

The square root of 1281530681 is about 35798.4731657650. The cubic root of 1281530681 is about 1086.1996770925.

The spelling of 1281530681 in words is "one billion, two hundred eighty-one million, five hundred thirty thousand, six hundred eighty-one".