1211540451 has 12 divisors (see below), whose sum is σ = 1775591496. Its totient is φ = 734266720.

The previous prime is 1211540441. The next prime is 1211540467. The reversal of 1211540451 is 1540451121.

It is not a de Polignac number, because 1211540451 - 2⁹ = 1211539939 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211540441) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1668426 + ... + 1669151.

It is an arithmetic number, because the mean of its divisors is an integer number (147965958).

Almost surely, 2^1211540451 is an apocalyptic number.

1211540451 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1211540451 is a deficient number, since it is larger than the sum of its proper divisors (564051045).

1211540451 is a wasteful number, since it uses less digits than its factorization.

1211540451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3337602 (or 3337591 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 24.

The square root of 1211540451 is about 34807.1896452443. The cubic root of 1211540451 is about 1066.0542510703.

Adding to 1211540451 its reverse (1540451121), we get a palindrome (2751991572).

The spelling of 1211540451 in words is "one billion, two hundred eleven million, five hundred forty thousand, four hundred fifty-one".