1211550 has 48 divisors (see below), whose sum is σ = 3093552. Its totient is φ = 313600.

The previous prime is 1211549. The next prime is 1211563. The reversal of 1211550 is 551121.

It is a super-4 number, since 4×1211550⁴ (a number of 25 digits) contains 4444 as substring. Note that it is a super-d number also for d = 3.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6052 + ... + 6248.

It is an arithmetic number, because the mean of its divisors is an integer number (64449).

2^1211550 is an apocalyptic number.

1211550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1546776).

1211550 is an abundant number, since it is smaller than the sum of its proper divisors (1882002).

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

1211550 is a wasteful number, since it uses less digits than its factorization.

1211550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253 (or 248 counting only the distinct ones).

The product of its (nonzero) digits is 50, while the sum is 15.

The square root of 1211550 is about 1100.7043199697. The cubic root of 1211550 is about 106.6057051837.

Adding to 1211550 its reverse (551121), we get a palindrome (1762671).

The spelling of 1211550 in words is "one million, two hundred eleven thousand, five hundred fifty".