1361638656 has 216 divisors, whose sum is σ = 4581012800. Its totient is φ = 388813824.

The previous prime is 1361638631. The next prime is 1361638661. The reversal of 1361638656 is 6568361631.

1361638656 is a `hidden beast` number, since 1 + 3 + 6 + 1 + 638 + 6 + 5 + 6 = 666.

It is a nialpdrome in base 14.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 789411 + ... + 791133.

Almost surely, 2^1361638656 is an apocalyptic number.

1361638656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1361638656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2290506400).

1361638656 is an abundant number, since it is smaller than the sum of its proper divisors (3219374144).

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

1361638656 is an equidigital number, since it uses as much as digits as its factorization.

1361638656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1766 (or 1735 counting only the distinct ones).

The product of its digits is 466560, while the sum is 45.

The square root of 1361638656 is about 36900.3882906400. The cubic root of 1361638656 is about 1108.3764528623.

The spelling of 1361638656 in words is "one billion, three hundred sixty-one million, six hundred thirty-eight thousand, six hundred fifty-six".