900999391 has 4 divisors (see below), whose sum is σ = 904324384. Its totient is φ = 897674400.

The previous prime is 900999383. The next prime is 900999403. The reversal of 900999391 is 193999009.

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 900999391 - 2³ = 900999383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (900999331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1662090 + ... + 1662631.

It is an arithmetic number, because the mean of its divisors is an integer number (226081096).

Almost surely, 2^900999391 is an apocalyptic number.

900999391 is a deficient number, since it is larger than the sum of its proper divisors (3324993).

900999391 is a wasteful number, since it uses less digits than its factorization.

900999391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3324992.

The product of its (nonzero) digits is 177147, while the sum is 49.

The square root of 900999391 is about 30016.6518952397. The cubic root of 900999391 is about 965.8466232977.

The spelling of 900999391 in words is "nine hundred million, nine hundred ninety-nine thousand, three hundred ninety-one".