1286951844721 has 9 divisors (see below), whose sum is σ = 1314970873099. Its totient is φ = 1259517706384.

The previous prime is 1286951844719. The next prime is 1286951844733. The reversal of 1286951844721 is 1274481596821.

It is a happy number.

The square root of 1286951844721 is 1134439.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 907170527025 + 379781317696 = 952455^2 + 616264^2 .

It is not a de Polignac number, because 1286951844721 - 2¹ = 1286951844719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1286951844121) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 53306565 + ... + 53330701.

Almost surely, 2^{1286951844721} is an apocalyptic number.

1286951844721 is the 1134439-th square number.

1286951844721 is the 567220-th centered octagonal number.

It is an amenable number.

1286951844721 is a deficient number, since it is larger than the sum of its proper divisors (28019028378).

1286951844721 is an frugal number, since it uses more digits than its factorization.

1286951844721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48368 (or 24184 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 58.

The spelling of 1286951844721 in words is "one trillion, two hundred eighty-six billion, nine hundred fifty-one million, eight hundred forty-four thousand, seven hundred twenty-one".