9977661 has 20 divisors (see below), whose sum is σ = 15004000. Its totient is φ = 6607656.

The previous prime is 9977659. The next prime is 9977683. The reversal of 9977661 is 1667799.

It is not a de Polignac number, because 9977661 - 2¹ = 9977659 is a prime.

It is a Duffinian number.

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 (9977651) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 15810 + ... + 16428.

It is an arithmetic number, because the mean of its divisors is an integer number (750200).

Almost surely, 2^9977661 is an apocalyptic number.

It is an amenable number.

9977661 is a deficient number, since it is larger than the sum of its proper divisors (5026339).

9977661 is a wasteful number, since it uses less digits than its factorization.

9977661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 830 (or 821 counting only the distinct ones).

The product of its digits is 142884, while the sum is 45.

The square root of 9977661 is about 3158.7435793366. The cubic root of 9977661 is about 215.2829230074.

The spelling of 9977661 in words is "nine million, nine hundred seventy-seven thousand, six hundred sixty-one".