136521 has 24 divisors (see below), whose sum is σ = 247104. Its totient is φ = 70560.

The previous prime is 136519. The next prime is 136523. The reversal of 136521 is 125631.

136521 is a `hidden beast` number, since 13 + 652 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (136519) and next prime (136523).

It is not a de Polignac number, because 136521 - 2¹ = 136519 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 136494 and 136503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 595 + ... + 791.

It is an arithmetic number, because the mean of its divisors is an integer number (10296).

2¹³⁶⁵²¹ is an apocalyptic number.

136521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

136521 is a deficient number, since it is larger than the sum of its proper divisors (110583).

136521 is a wasteful number, since it uses less digits than its factorization.

136521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221 (or 218 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 136521 is about 369.4874828732. The cubic root of 136521 is about 51.4912166502.

Subtracting from 136521 its sum of digits (18), we obtain a triangular number (136503 = T₅₂₂).

The spelling of 136521 in words is "one hundred thirty-six thousand, five hundred twenty-one".