9887661 has 24 divisors (see below), whose sum is σ = 16660800. Its totient is φ = 5648328.

The previous prime is 9887653. The next prime is 9887663. The reversal of 9887661 is 1667889.

It is a happy number.

It is not a de Polignac number, because 9887661 - 2³ = 9887653 is a prime.

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 (9887663) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1486 + ... + 4688.

It is an arithmetic number, because the mean of its divisors is an integer number (694200).

Almost surely, 2^9887661 is an apocalyptic number.

It is an amenable number.

9887661 is a deficient number, since it is larger than the sum of its proper divisors (6773139).

9887661 is a wasteful number, since it uses less digits than its factorization.

9887661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3230 (or 3213 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 9887661 is about 3144.4651373485. The cubic root of 9887661 is about 214.6336722027.

It can be divided in two parts, 988 and 7661, that added together give a square (8649 = 93²).

The spelling of 9887661 in words is "nine million, eight hundred eighty-seven thousand, six hundred sixty-one".