1361388581 has 8 divisors (see below), whose sum is σ = 1585229184. Its totient is φ = 1144887120.

The previous prime is 1361388571. The next prime is 1361388583. The reversal of 1361388581 is 1858831631.

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-1361388581 is a prime.

It is a super-2 number, since 2×1361388581² = 3706757736954387122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361388583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1834385 + ... + 1835126.

It is an arithmetic number, because the mean of its divisors is an integer number (198153648).

Almost surely, 2^1361388581 is an apocalyptic number.

It is an amenable number.

1361388581 is a deficient number, since it is larger than the sum of its proper divisors (223840603).

1361388581 is an equidigital number, since it uses as much as digits as its factorization.

1361388581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3669571.

The product of its digits is 138240, while the sum is 44.

The square root of 1361388581 is about 36896.9996205654. Note that the first 3 decimals coincide. The cubic root of 1361388581 is about 1108.3085948662.

The spelling of 1361388581 in words is "one billion, three hundred sixty-one million, three hundred eighty-eight thousand, five hundred eighty-one".