987209131 has 4 divisors (see below), whose sum is σ = 987335200. Its totient is φ = 987083064.

The previous prime is 987209129. The next prime is 987209137. The reversal of 987209131 is 131902789.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 131902789 = 3049 ⋅43261.

It is a cyclic number.

It is not a de Polignac number, because 987209131 - 2¹ = 987209129 is a prime.

It is a super-2 number, since 2×987209131² = 1949163736659550322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (987209137) 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, 50451 + ... + 67228.

It is an arithmetic number, because the mean of its divisors is an integer number (246833800).

Almost surely, 2^987209131 is an apocalyptic number.

987209131 is a deficient number, since it is larger than the sum of its proper divisors (126069).

987209131 is a wasteful number, since it uses less digits than its factorization.

987209131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126068.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 987209131 is about 31419.8843250576. The cubic root of 987209131 is about 995.7180682300.

The spelling of 987209131 in words is "nine hundred eighty-seven million, two hundred nine thousand, one hundred thirty-one".