1205542140 has 96 divisors (see below), whose sum is σ = 3781983744. Its totient is φ = 284348160.

The previous prime is 1205542139. The next prime is 1205542159. The reversal of 1205542140 is 412455021.

It is a self number, because there is not a number n which added to its sum of digits gives 1205542140.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 264 + ... + 49103.

It is an arithmetic number, because the mean of its divisors is an integer number (39395664).

Almost surely, 2^1205542140 is an apocalyptic number.

1205542140 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 1205542140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1890991872).

1205542140 is an abundant number, since it is smaller than the sum of its proper divisors (2576441604).

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

1205542140 is a wasteful number, since it uses less digits than its factorization.

1205542140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49427 (or 49425 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 24.

The square root of 1205542140 is about 34720.9179026131. The cubic root of 1205542140 is about 1064.2920022708.

Adding to 1205542140 its reverse (412455021), we get a palindrome (1617997161).

It can be divided in two parts, 1205 and 542140, that added together give a palindrome (543345).

The spelling of 1205542140 in words is "one billion, two hundred five million, five hundred forty-two thousand, one hundred forty".