987487691 has 4 divisors (see below), whose sum is σ = 987654384. Its totient is φ = 987321000.

The previous prime is 987487649. The next prime is 987487723. The reversal of 987487691 is 196784789.

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-987487691 is a prime.

It is a super-2 number, since 2×987487691² = 1950263879753022962, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 987487691.

It is not an unprimeable number, because it can be changed into a prime (987487601) 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, 74120 + ... + 86421.

It is an arithmetic number, because the mean of its divisors is an integer number (246913596).

Almost surely, 2^987487691 is an apocalyptic number.

987487691 is a deficient number, since it is larger than the sum of its proper divisors (166693).

987487691 is a wasteful number, since it uses less digits than its factorization.

987487691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166692.

The product of its digits is 6096384, while the sum is 59.

The square root of 987487691 is about 31424.3168740388. The cubic root of 987487691 is about 995.8117130759.

The spelling of 987487691 in words is "nine hundred eighty-seven million, four hundred eighty-seven thousand, six hundred ninety-one".