1641233440 has 144 divisors (see below), whose sum is σ = 4920761664. Its totient is φ = 511526400.

The previous prime is 1641233411. The next prime is 1641233443. The reversal of 1641233440 is 443321461.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 1641233399 and 1641233408.

It is not an unprimeable number, because it can be changed into a prime (1641233443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 76725 + ... + 95755.

It is an arithmetic number, because the mean of its divisors is an integer number (34171956).

Almost surely, 2^1641233440 is an apocalyptic number.

1641233440 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 1641233440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2460380832).

1641233440 is an abundant number, since it is smaller than the sum of its proper divisors (3279528224).

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

1641233440 is a wasteful number, since it uses less digits than its factorization.

1641233440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19071 (or 19056 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 1641233440 is about 40512.1394152419. The cubic root of 1641233440 is about 1179.5692768674.

The spelling of 1641233440 in words is "one billion, six hundred forty-one million, two hundred thirty-three thousand, four hundred forty".