1211423040 has 252 divisors, whose sum is σ = 4334330676. Its totient is φ = 322486272.

The previous prime is 1211423027. The next prime is 1211423063. The reversal of 1211423040 is 403241121.

It can be written as a sum of positive squares in 2 ways, for example, as 927567936 + 283855104 = 30456^2 + 16848^2 .

It is a super-3 number, since 3×1211423040³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2099232 + ... + 2099808.

Almost surely, 2^1211423040 is an apocalyptic number.

1211423040 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 1211423040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2167165338).

1211423040 is an abundant number, since it is smaller than the sum of its proper divisors (3122907636).

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

1211423040 is an frugal number, since it uses more digits than its factorization.

1211423040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618 (or 587 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1211423040 is about 34805.5030131731. The cubic root of 1211423040 is about 1066.0198126716.

Adding to 1211423040 its reverse (403241121), we get a palindrome (1614664161).

The spelling of 1211423040 in words is "one billion, two hundred eleven million, four hundred twenty-three thousand, forty".