1365136821 has 24 divisors (see below), whose sum is σ = 2047456320. Its totient is φ = 908952192.

The previous prime is 1365136753. The next prime is 1365136837. The reversal of 1365136821 is 1286315631.

1365136821 is a `hidden beast` number, since 136 + 513 + 6 + 8 + 2 + 1 = 666.

It is not a de Polignac number, because 1365136821 - 2⁷ = 1365136693 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1365136321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 220261 + ... + 226373.

It is an arithmetic number, because the mean of its divisors is an integer number (85310680).

Almost surely, 2^1365136821 is an apocalyptic number.

It is an amenable number.

1365136821 is a deficient number, since it is larger than the sum of its proper divisors (682319499).

1365136821 is an frugal number, since it uses more digits than its factorization.

1365136821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7047 (or 7035 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 1365136821 is about 36947.7579969340. The cubic root of 1365136821 is about 1109.3248121722.

The spelling of 1365136821 in words is "one billion, three hundred sixty-five million, one hundred thirty-six thousand, eight hundred twenty-one".