1211166415 has 4 divisors (see below), whose sum is σ = 1453399704. Its totient is φ = 968933128.

The previous prime is 1211166413. The next prime is 1211166443. The reversal of 1211166415 is 5146611121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5146611121 = 29 ⋅177469349.

It is a cyclic number.

It is not a de Polignac number, because 1211166415 - 2¹ = 1211166413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211166413) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121116637 + ... + 121116646.

It is an arithmetic number, because the mean of its divisors is an integer number (363349926).

Almost surely, 2^1211166415 is an apocalyptic number.

1211166415 is a deficient number, since it is larger than the sum of its proper divisors (242233289).

1211166415 is an equidigital number, since it uses as much as digits as its factorization.

1211166415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242233288.

The product of its digits is 1440, while the sum is 28.

The square root of 1211166415 is about 34801.8162600747. The cubic root of 1211166415 is about 1065.9445329812.

Adding to 1211166415 its reverse (5146611121), we get a palindrome (6357777536).

The spelling of 1211166415 in words is "one billion, two hundred eleven million, one hundred sixty-six thousand, four hundred fifteen".