8781961 has 4 divisors (see below), whose sum is σ = 8788500. Its totient is φ = 8775424.

The previous prime is 8781953. The next prime is 8781967. The reversal of 8781961 is 1691878.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 6943225 + 1838736 = 2635^2 + 1356^2 .

It is a cyclic number.

It is not a de Polignac number, because 8781961 - 2³ = 8781953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8781967) 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, 436 + ... + 4213.

It is an arithmetic number, because the mean of its divisors is an integer number (2197125).

Almost surely, 2^8781961 is an apocalyptic number.

It is an amenable number.

8781961 is a deficient number, since it is larger than the sum of its proper divisors (6539).

8781961 is a wasteful number, since it uses less digits than its factorization.

8781961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6538.

The product of its digits is 24192, while the sum is 40.

The square root of 8781961 is about 2963.4373622535. The cubic root of 8781961 is about 206.3148561264.

The spelling of 8781961 in words is "eight million, seven hundred eighty-one thousand, nine hundred sixty-one".