1205073640 has 64 divisors (see below), whose sum is σ = 2785602960. Its totient is φ = 468910080.

The previous prime is 1205073631. The next prime is 1205073647. The reversal of 1205073640 is 463705021.

It can be written as a sum of positive squares in 8 ways, for example, as 282979684 + 922093956 = 16822^2 + 30366^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1205073599 and 1205073608.

It is not an unprimeable number, because it can be changed into a prime (1205073647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 709272 + ... + 710968.

Almost surely, 2^1205073640 is an apocalyptic number.

1205073640 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 1205073640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1392801480).

1205073640 is an abundant number, since it is smaller than the sum of its proper divisors (1580529320).

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

1205073640 is a wasteful number, since it uses less digits than its factorization.

1205073640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2182 (or 2178 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 1205073640 is about 34714.1705935775. The cubic root of 1205073640 is about 1064.1541153699.

Adding to 1205073640 its reverse (463705021), we get a palindrome (1668778661).

The spelling of 1205073640 in words is "one billion, two hundred five million, seventy-three thousand, six hundred forty".