961788091 has 4 divisors (see below), whose sum is σ = 1049223384. Its totient is φ = 874352800.

The previous prime is 961788089. The next prime is 961788167. The reversal of 961788091 is 190887169.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 961788091 - 2¹ = 961788089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (961788001) 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, 43717630 + ... + 43717651.

It is an arithmetic number, because the mean of its divisors is an integer number (262305846).

Almost surely, 2^961788091 is an apocalyptic number.

961788091 is a deficient number, since it is larger than the sum of its proper divisors (87435293).

961788091 is a wasteful number, since it uses less digits than its factorization.

961788091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87435292.

The product of its (nonzero) digits is 217728, while the sum is 49.

The square root of 961788091 is about 31012.7085402098. The cubic root of 961788091 is about 987.0969236970.

The spelling of 961788091 in words is "nine hundred sixty-one million, seven hundred eighty-eight thousand, ninety-one".