1609838720 has 128 divisors (see below), whose sum is σ = 4550342400. Its totient is φ = 532869120.

The previous prime is 1609838717. The next prime is 1609838723. The reversal of 1609838720 is 278389061.

It is an interprime number because it is at equal distance from previous prime (1609838717) and next prime (1609838723).

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×1609838720² = 5183161408822476800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1609838723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 123725 + ... + 136115.

It is an arithmetic number, because the mean of its divisors is an integer number (35549550).

Almost surely, 2^1609838720 is an apocalyptic number.

1609838720 is a gapful number since it is divisible by the number (10) 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 1609838720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2275171200).

1609838720 is an abundant number, since it is smaller than the sum of its proper divisors (2940503680).

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

1609838720 is a wasteful number, since it uses less digits than its factorization.

1609838720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12446 (or 12434 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 1609838720 is about 40122.7955157663. The cubic root of 1609838720 is about 1171.9995806589. Note that the first 3 decimals are identical.

The spelling of 1609838720 in words is "one billion, six hundred nine million, eight hundred thirty-eight thousand, seven hundred twenty".