9961987 has 8 divisors (see below), whose sum is σ = 11446272. Its totient is φ = 8493000.

The previous prime is 9961981. The next prime is 9962003. The reversal of 9961987 is 7891699.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9961987 - 2²³ = 1573379 is a prime.

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 9961987.

It is not an unprimeable number, because it can be changed into a prime (9961981) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2389 + ... + 5062.

It is an arithmetic number, because the mean of its divisors is an integer number (1430784).

Almost surely, 2^9961987 is an apocalyptic number.

9961987 is a deficient number, since it is larger than the sum of its proper divisors (1484285).

9961987 is a wasteful number, since it uses less digits than its factorization.

9961987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7649.

The product of its digits is 244944, while the sum is 49.

The square root of 9961987 is about 3156.2615544343. The cubic root of 9961987 is about 215.1701339476.

The spelling of 9961987 in words is "nine million, nine hundred sixty-one thousand, nine hundred eighty-seven".