1356617681 has 4 divisors (see below), whose sum is σ = 1360035252. Its totient is φ = 1353200112.

The previous prime is 1356617677. The next prime is 1356617711. The reversal of 1356617681 is 1867166531.

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

It can be written as a sum of positive squares in 2 ways, for example, as 538657681 + 817960000 = 23209^2 + 28600^2 .

It is a cyclic number.

It is not a de Polignac number, because 1356617681 - 2² = 1356617677 is a prime.

It is a super-3 number, since 3×1356617681³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1356617611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1708190 + ... + 1708983.

It is an arithmetic number, because the mean of its divisors is an integer number (340008813).

Almost surely, 2^1356617681 is an apocalyptic number.

It is an amenable number.

1356617681 is a deficient number, since it is larger than the sum of its proper divisors (3417571).

1356617681 is an equidigital number, since it uses as much as digits as its factorization.

1356617681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3417570.

The product of its digits is 181440, while the sum is 44.

The square root of 1356617681 is about 36832.2912808856. The cubic root of 1356617681 is about 1107.0124138141.

The spelling of 1356617681 in words is "one billion, three hundred fifty-six million, six hundred seventeen thousand, six hundred eighty-one".