899987778 has 48 divisors (see below), whose sum is σ = 2035598136. Its totient is φ = 287089920.

The previous prime is 899987773. The next prime is 899987783. The reversal of 899987778 is 877789998.

It is an interprime number because it is at equal distance from previous prime (899987773) and next prime (899987783).

It can be written as a sum of positive squares in 4 ways, for example, as 490046769 + 409941009 = 22137^2 + 20247^2 .

It is a super-3 number, since 3×899987778³ (a number of 28 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (899987771) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29550 + ... + 51702.

Almost surely, 2^899987778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 899987778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1017799068).

899987778 is an abundant number, since it is smaller than the sum of its proper divisors (1135610358).

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

899987778 is a wasteful number, since it uses less digits than its factorization.

899987778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22259 (or 22256 counting only the distinct ones).

The product of its digits is 128024064, while the sum is 72.

The square root of 899987778 is about 29999.7962993084. The cubic root of 899987778 is about 965.4850141372.

The spelling of 899987778 in words is "eight hundred ninety-nine million, nine hundred eighty-seven thousand, seven hundred seventy-eight".