1211530340 has 24 divisors (see below), whose sum is σ = 2545424952. Its totient is φ = 484381440.

The previous prime is 1211530337. The next prime is 1211530349. The reversal of 1211530340 is 430351121.

It can be written as a sum of positive squares in 4 ways, for example, as 141324544 + 1070205796 = 11888^2 + 32714^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (1211530349) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32342 + ... + 58898.

It is an arithmetic number, because the mean of its divisors is an integer number (106059373).

Almost surely, 2^1211530340 is an apocalyptic number.

1211530340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211530340 is an abundant number, since it is smaller than the sum of its proper divisors (1333894612).

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

1211530340 is a wasteful number, since it uses less digits than its factorization.

1211530340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28847 (or 28845 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 1211530340 is about 34807.0444019598. The cubic root of 1211530340 is about 1066.0512854506.

Adding to 1211530340 its reverse (430351121), we get a palindrome (1641881461).

The spelling of 1211530340 in words is "one billion, two hundred eleven million, five hundred thirty thousand, three hundred forty".