1211255424 has 128 divisors (see below), whose sum is σ = 3651436800. Its totient is φ = 395108352.

The previous prime is 1211255411. The next prime is 1211255431. The reversal of 1211255424 is 4245521121.

It is a happy number.

1211255424 is a `hidden beast` number, since 1 + 2 + 112 + 5 + 542 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 158704 + ... + 166160.

It is an arithmetic number, because the mean of its divisors is an integer number (28526850).

Almost surely, 2^1211255424 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211255424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1825718400).

1211255424 is an abundant number, since it is smaller than the sum of its proper divisors (2440181376).

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

1211255424 is an equidigital number, since it uses as much as digits as its factorization.

1211255424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7527 (or 7509 counting only the distinct ones).

The product of its digits is 3200, while the sum is 27.

The square root of 1211255424 is about 34803.0950347810. The cubic root of 1211255424 is about 1065.9706445410.

Adding to 1211255424 its reverse (4245521121), we get a palindrome (5456776545).

The spelling of 1211255424 in words is "one billion, two hundred eleven million, two hundred fifty-five thousand, four hundred twenty-four".