87691521 has 8 divisors (see below), whose sum is σ = 119128320. Its totient is φ = 57357872.

The previous prime is 87691493. The next prime is 87691537. The reversal of 87691521 is 12519678.

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

It is not a de Polignac number, because 87691521 - 2¹⁰ = 87690497 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 87691521.

It is not an unprimeable number, because it can be changed into a prime (87691421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 275601 + ... + 275918.

It is an arithmetic number, because the mean of its divisors is an integer number (14891040).

Almost surely, 2^87691521 is an apocalyptic number.

It is an amenable number.

87691521 is a deficient number, since it is larger than the sum of its proper divisors (31436799).

87691521 is a wasteful number, since it uses less digits than its factorization.

87691521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 551575.

The product of its digits is 30240, while the sum is 39.

The square root of 87691521 is about 9364.3750992792. The cubic root of 87691521 is about 444.2756739040.

The spelling of 87691521 in words is "eighty-seven million, six hundred ninety-one thousand, five hundred twenty-one".