87831491 has 4 divisors (see below), whose sum is σ = 95816184. Its totient is φ = 79846800.

The previous prime is 87831467. The next prime is 87831511. The reversal of 87831491 is 19413878.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 87831491 - 2⁶ = 87831427 is a prime.

It is a super-2 number, since 2×87831491² = 15428741622566162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87831421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3992330 + ... + 3992351.

It is an arithmetic number, because the mean of its divisors is an integer number (23954046).

Almost surely, 2^87831491 is an apocalyptic number.

87831491 is a deficient number, since it is larger than the sum of its proper divisors (7984693).

87831491 is a wasteful number, since it uses less digits than its factorization.

87831491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7984692.

The product of its digits is 48384, while the sum is 41.

The square root of 87831491 is about 9371.8456560061. The cubic root of 87831491 is about 444.5119271120.

The spelling of 87831491 in words is "eighty-seven million, eight hundred thirty-one thousand, four hundred ninety-one".