9900381 has 4 divisors (see below), whose sum is σ = 13200512. Its totient is φ = 6600252.

The previous prime is 9900379. The next prime is 9900391. The reversal of 9900381 is 1830099.

It is a happy number.

9900381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 9900381 - 2¹ = 9900379 is a prime.

It is a super-2 number, since 2×9900381² = 196035087890322, which contains 22 as substring.

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 (9900301) 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, 1650061 + ... + 1650066.

It is an arithmetic number, because the mean of its divisors is an integer number (3300128).

Almost surely, 2^9900381 is an apocalyptic number.

It is an amenable number.

9900381 is a deficient number, since it is larger than the sum of its proper divisors (3300131).

9900381 is a wasteful number, since it uses less digits than its factorization.

9900381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3300130.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 9900381 is about 3146.4870888024. The cubic root of 9900381 is about 214.7256713929.

The spelling of 9900381 in words is "nine million, nine hundred thousand, three hundred eighty-one".