909999400 has 72 divisors (see below), whose sum is σ = 2163050730. Its totient is φ = 355912960.

The previous prime is 909999397. The next prime is 909999407. The reversal of 909999400 is 4999909.

It can be written as a sum of positive squares in 9 ways, for example, as 572836356 + 337163044 = 23934^2 + 18362^2 .

It is not an unprimeable number, because it can be changed into a prime (909999407) 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 17 ways as a sum of consecutive naturals, for example, 3105654 + ... + 3105946.

Almost surely, 2^909999400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 909999400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1081525365).

909999400 is an abundant number, since it is smaller than the sum of its proper divisors (1253051330).

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

909999400 is a wasteful number, since it uses less digits than its factorization.

909999400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 655 (or 353 counting only the distinct ones).

The product of its (nonzero) digits is 236196, while the sum is 49.

The square root of 909999400 is about 30166.1963130919. The cubic root of 909999400 is about 969.0518953648.

The spelling of 909999400 in words is "nine hundred nine million, nine hundred ninety-nine thousand, four hundred".