9941165781 has 8 divisors (see below), whose sum is σ = 13328938080. Its totient is φ = 6590418672.

The previous prime is 9941165771. The next prime is 9941165797. The reversal of 9941165781 is 1875611499.

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

It is not a de Polignac number, because 9941165781 - 2¹⁴ = 9941149397 is a prime.

It is a super-2 number, since 2×9941165781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9941165771) 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, 9255670 + ... + 9256743.

It is an arithmetic number, because the mean of its divisors is an integer number (1666117260).

Almost surely, 2^9941165781 is an apocalyptic number.

It is an amenable number.

9941165781 is a deficient number, since it is larger than the sum of its proper divisors (3387772299).

9941165781 is a wasteful number, since it uses less digits than its factorization.

9941165781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18512595.

The product of its digits is 544320, while the sum is 51.

The square root of 9941165781 is about 99705.3949443058. The cubic root of 9941165781 is about 2150.2012273168.

The spelling of 9941165781 in words is "nine billion, nine hundred forty-one million, one hundred sixty-five thousand, seven hundred eighty-one".