87836721 has 8 divisors (see below), whose sum is σ = 133846464. Its totient is φ = 50192400.

The previous prime is 87836687. The next prime is 87836729. The reversal of 87836721 is 12763878.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 87836721 - 2⁶ = 87836657 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (87836729) 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, 2091330 + ... + 2091371.

It is an arithmetic number, because the mean of its divisors is an integer number (16730808).

Almost surely, 2^87836721 is an apocalyptic number.

It is an amenable number.

87836721 is a deficient number, since it is larger than the sum of its proper divisors (46009743).

87836721 is a wasteful number, since it uses less digits than its factorization.

87836721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4182711.

The product of its digits is 112896, while the sum is 42.

The square root of 87836721 is about 9372.1246790682. The cubic root of 87836721 is about 444.5207498824.

The spelling of 87836721 in words is "eighty-seven million, eight hundred thirty-six thousand, seven hundred twenty-one".