87912921 has 8 divisors (see below), whose sum is σ = 118112544. Its totient is φ = 58160960.

The previous prime is 87912919. The next prime is 87912961. The reversal of 87912921 is 12921978.

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

It is a cyclic number.

It is not a de Polignac number, because 87912921 - 2¹ = 87912919 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 87912921.

It is not an unprimeable number, because it can be changed into a prime (87912901) 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, 111456 + ... + 112241.

It is an arithmetic number, because the mean of its divisors is an integer number (14764068).

Almost surely, 2^87912921 is an apocalyptic number.

It is an amenable number.

87912921 is a deficient number, since it is larger than the sum of its proper divisors (30199623).

87912921 is a wasteful number, since it uses less digits than its factorization.

87912921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223831.

The product of its digits is 18144, while the sum is 39.

The square root of 87912921 is about 9376.1890445959. The cubic root of 87912921 is about 444.6492560867.

The spelling of 87912921 in words is "eighty-seven million, nine hundred twelve thousand, nine hundred twenty-one".