1649984400 has 135 divisors (see below), whose sum is σ = 5734374451. Its totient is φ = 439345920.

The previous prime is 1649984389. The next prime is 1649984417. The reversal of 1649984400 is 44899461.

The square root of 1649984400 is 40620.

It is a perfect power (a square), and thus also a powerful number.

1649984400 is a `hidden beast` number, since 164 + 9 + 9 + 84 + 400 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 475414416 + 1174569984 = 21804^2 + 34272^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Duffinian number.

It is a zygodrome in base 15.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2436862 + ... + 2437538.

Almost surely, 2^1649984400 is an apocalyptic number.

1649984400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1649984400 is the 40620-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1649984400

1649984400 is an abundant number, since it is smaller than the sum of its proper divisors (4084390051).

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

1649984400 is an equidigital number, since it uses as much as digits as its factorization.

1649984400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1378 (or 687 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The cubic root of 1649984400 is about 1181.6620264182.

It can be divided in two parts, 1649 and 984400, that added together give a square (986049 = 993²).

The spelling of 1649984400 in words is "one billion, six hundred forty-nine million, nine hundred eighty-four thousand, four hundred".