87938991 has 48 divisors (see below), whose sum is σ = 151756800. Its totient is φ = 48009024.

The previous prime is 87938953. The next prime is 87938993. The reversal of 87938991 is 19983978.

It is not a de Polignac number, because 87938991 - 2¹⁴ = 87922607 is a prime.

It is a super-2 number, since 2×87938991² = 15466532276196162, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87938993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 231840 + ... + 232218.

It is an arithmetic number, because the mean of its divisors is an integer number (3161600).

Almost surely, 2^87938991 is an apocalyptic number.

87938991 is a deficient number, since it is larger than the sum of its proper divisors (63817809).

87938991 is a wasteful number, since it uses less digits than its factorization.

87938991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548 (or 545 counting only the distinct ones).

The product of its digits is 979776, while the sum is 54.

The square root of 87938991 is about 9377.5791652217. The cubic root of 87938991 is about 444.6932043495.

The spelling of 87938991 in words is "eighty-seven million, nine hundred thirty-eight thousand, nine hundred ninety-one".