9910991901 has 4 divisors (see below), whose sum is σ = 13214655872. Its totient is φ = 6607327932.

The previous prime is 9910991899. The next prime is 9910991911. The reversal of 9910991901 is 1091990199.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 9910991901 - 2¹ = 9910991899 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9910991911) 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, 1651831981 + ... + 1651831986.

It is an arithmetic number, because the mean of its divisors is an integer number (3303663968).

Almost surely, 2^9910991901 is an apocalyptic number.

It is an amenable number.

9910991901 is a deficient number, since it is larger than the sum of its proper divisors (3303663971).

9910991901 is a wasteful number, since it uses less digits than its factorization.

9910991901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3303663970.

The product of its (nonzero) digits is 59049, while the sum is 48.

The square root of 9910991901 is about 99553.9647678584. The cubic root of 9910991901 is about 2148.0235596163.

The spelling of 9910991901 in words is "nine billion, nine hundred ten million, nine hundred ninety-one thousand, nine hundred one".