8400400000 has 96 divisors (see below), whose sum is σ = 20918622060. Its totient is φ = 3360000000.

The previous prime is 8400399949. The next prime is 8400400049. The reversal of 8400400000 is 40048.

It can be written as a sum of positive squares in 6 ways, for example, as 1973491776 + 6426908224 = 44424^2 + 80168^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 389500 + ... + 410500.

Almost surely, 2^8400400000 is an apocalyptic number.

8400400000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8400400000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10459311030).

8400400000 is an abundant number, since it is smaller than the sum of its proper divisors (12518222060).

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

8400400000 is an frugal number, since it uses more digits than its factorization.

8400400000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21040 (or 21008 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 8400400000 is about 91653.6960520415. The cubic root of 8400400000 is about 2032.8249796686.

Adding to 8400400000 its reverse (40048), we get a palindrome (8400440048).

The spelling of 8400400000 in words is "eight billion, four hundred million, four hundred thousand".