1211822136 has 144 divisors (see below), whose sum is σ = 3832007400. Its totient is φ = 344953728.

The previous prime is 1211822123. The next prime is 1211822141. The reversal of 1211822136 is 6312281121.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1371951 + ... + 1372833.

Almost surely, 2^1211822136 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 1211822136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1916003700).

1211822136 is an abundant number, since it is smaller than the sum of its proper divisors (2620185264).

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

1211822136 is a wasteful number, since it uses less digits than its factorization.

1211822136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1298 (or 1284 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 1211822136 is about 34811.2357723767. The cubic root of 1211822136 is about 1066.1368644137.

The spelling of 1211822136 in words is "one billion, two hundred eleven million, eight hundred twenty-two thousand, one hundred thirty-six".