1125221111 has 32 divisors (see below), whose sum is σ = 1377285120. Its totient is φ = 898470144.

The previous prime is 1125221107. The next prime is 1125221113. The reversal of 1125221111 is 1111225211.

It is a cyclic number.

It is not a de Polignac number, because 1125221111 - 2² = 1125221107 is a prime.

It is a super-4 number, since 4×1125221111⁴ (a number of 37 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1125221111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1125221113) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1390475 + ... + 1391283.

It is an arithmetic number, because the mean of its divisors is an integer number (43040160).

Almost surely, 2^1125221111 is an apocalyptic number.

1125221111 is a deficient number, since it is larger than the sum of its proper divisors (252064009).

1125221111 is a wasteful number, since it uses less digits than its factorization.

1125221111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1055.

The product of its digits is 40, while the sum is 17.

The square root of 1125221111 is about 33544.3156287321. The cubic root of 1125221111 is about 1040.1100447534.

Adding to 1125221111 its reverse (1111225211), we get a palindrome (2236446322).

The spelling of 1125221111 in words is "one billion, one hundred twenty-five million, two hundred twenty-one thousand, one hundred eleven".