9919642866 has 32 divisors (see below), whose sum is σ = 22692216960. Its totient is φ = 2831840256.

The previous prime is 9919642861. The next prime is 9919642891. The reversal of 9919642866 is 6682469199.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9919642861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45921 + ... + 148148.

It is an arithmetic number, because the mean of its divisors is an integer number (709131780).

Almost surely, 2^9919642866 is an apocalyptic number.

9919642866 is an abundant number, since it is smaller than the sum of its proper divisors (12772574094).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9919642866 is a wasteful number, since it uses less digits than its factorization.

9919642866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195298.

The product of its digits is 10077696, while the sum is 60.

The square root of 9919642866 is about 99597.4039119494. The cubic root of 9919642866 is about 2148.6483565680.

The spelling of 9919642866 in words is "nine billion, nine hundred nineteen million, six hundred forty-two thousand, eight hundred sixty-six".