1281221684 has 12 divisors (see below), whose sum is σ = 2270520000. Its totient is φ = 632501688.

The previous prime is 1281221659. The next prime is 1281221707. The reversal of 1281221684 is 4861221821.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2026934 + ... + 2027565.

It is an arithmetic number, because the mean of its divisors is an integer number (189210000).

Almost surely, 2^1281221684 is an apocalyptic number.

It is an amenable number.

1281221684 is a deficient number, since it is larger than the sum of its proper divisors (989298316).

1281221684 is a wasteful number, since it uses less digits than its factorization.

1281221684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4054582 (or 4054580 counting only the distinct ones).

The product of its digits is 12288, while the sum is 35.

The square root of 1281221684 is about 35794.1571209604. The cubic root of 1281221684 is about 1086.1123701905.

The spelling of 1281221684 in words is "one billion, two hundred eighty-one million, two hundred twenty-one thousand, six hundred eighty-four".