87931491 has 8 divisors (see below), whose sum is σ = 117961920. Its totient is φ = 58261032.

The previous prime is 87931483. The next prime is 87931549. The reversal of 87931491 is 19413978.

It is a happy number.

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

It is not a de Polignac number, because 87931491 - 2³ = 87931483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (87931421) 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, 89421 + ... + 90398.

It is an arithmetic number, because the mean of its divisors is an integer number (14745240).

Almost surely, 2^87931491 is an apocalyptic number.

87931491 is a deficient number, since it is larger than the sum of its proper divisors (30030429).

87931491 is a wasteful number, since it uses less digits than its factorization.

87931491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179985.

The product of its digits is 54432, while the sum is 42.

The square root of 87931491 is about 9377.1792667092. The cubic root of 87931491 is about 444.6805618958.

The spelling of 87931491 in words is "eighty-seven million, nine hundred thirty-one thousand, four hundred ninety-one".