121587 has 4 divisors (see below), whose sum is σ = 162120. Its totient is φ = 81056.

The previous prime is 121579. The next prime is 121591. The reversal of 121587 is 785121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 785121 = 3 ⋅261707.

It is a cyclic number.

It is not a de Polignac number, because 121587 - 2³ = 121579 is a prime.

It is a D-number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 121587.

It is not an unprimeable number, because it can be changed into a prime (121507) 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, 20262 + ... + 20267.

It is an arithmetic number, because the mean of its divisors is an integer number (40530).

2¹²¹⁵⁸⁷ is an apocalyptic number.

121587 is a deficient number, since it is larger than the sum of its proper divisors (40533).

121587 is an equidigital number, since it uses as much as digits as its factorization.

121587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40532.

The product of its digits is 560, while the sum is 24.

The square root of 121587 is about 348.6932749567. The cubic root of 121587 is about 49.5407276277.

It can be divided in two parts, 12 and 1587, that multiplied together give a square (19044 = 138²).

The spelling of 121587 in words is "one hundred twenty-one thousand, five hundred eighty-seven".