987431 has 4 divisors (see below), whose sum is σ = 996600. Its totient is φ = 978264.

The previous prime is 987391. The next prime is 987433. The reversal of 987431 is 134789.

987431 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-987431 is a prime.

It is a super-2 number, since 2×987431² = 1950039959522, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (987433) 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, 4421 + ... + 4638.

It is an arithmetic number, because the mean of its divisors is an integer number (249150).

2⁹⁸⁷⁴³¹ is an apocalyptic number.

987431 is a deficient number, since it is larger than the sum of its proper divisors (9169).

987431 is a wasteful number, since it uses less digits than its factorization.

987431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9168.

The product of its digits is 6048, while the sum is 32.

The square root of 987431 is about 993.6956274433. The cubic root of 987431 is about 99.5792656419.

The spelling of 987431 in words is "nine hundred eighty-seven thousand, four hundred thirty-one".