1281788680 has 32 divisors (see below), whose sum is σ = 2916437400. Its totient is φ = 506953216.

The previous prime is 1281788611. The next prime is 1281788693. The reversal of 1281788680 is 868871821.

It can be written as a sum of positive squares in 4 ways, for example, as 1012894276 + 268894404 = 31826^2 + 16398^2 .

It is a super-2 number, since 2×1281788680² = 3285964440352284800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 176467 + ... + 183586.

Almost surely, 2^1281788680 is an apocalyptic number.

1281788680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1281788680 is an abundant number, since it is smaller than the sum of its proper divisors (1634648720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1281788680 is a wasteful number, since it uses less digits than its factorization.

1281788680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360153 (or 360149 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 49.

The square root of 1281788680 is about 35802.0764760928. The cubic root of 1281788680 is about 1086.2725637924.

The spelling of 1281788680 in words is "one billion, two hundred eighty-one million, seven hundred eighty-eight thousand, six hundred eighty".