1011223121 has 4 divisors (see below), whose sum is σ = 1070706852. Its totient is φ = 951739392.

The previous prime is 1011223097. The next prime is 1011223133. The reversal of 1011223121 is 1213221101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1213221101 = 2087 ⋅581323.

It can be written as a sum of positive squares in 2 ways, for example, as 859662400 + 151560721 = 29320^2 + 12311^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1011223121 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1011223096 and 1011223105.

It is not an unprimeable number, because it can be changed into a prime (1011223141) 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, 29741840 + ... + 29741873.

It is an arithmetic number, because the mean of its divisors is an integer number (267676713).

Almost surely, 2^1011223121 is an apocalyptic number.

It is an amenable number.

1011223121 is a deficient number, since it is larger than the sum of its proper divisors (59483731).

1011223121 is an equidigital number, since it uses as much as digits as its factorization.

1011223121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59483730.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 1011223121 is about 31799.7346058108. The cubic root of 1011223121 is about 1003.7271315651.

Adding to 1011223121 its reverse (1213221101), we get a palindrome (2224444222).

It can be divided in two parts, 10112 and 23121, that added together give a palindrome (33233).

The spelling of 1011223121 in words is "one billion, eleven million, two hundred twenty-three thousand, one hundred twenty-one".