1131012221 has 4 divisors (see below), whose sum is σ = 1190539200. Its totient is φ = 1071485244.

The previous prime is 1131012191. The next prime is 1131012251. The reversal of 1131012221 is 1222101311.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1222101311 = 3257 ⋅375223.

It is an interprime number because it is at equal distance from previous prime (1131012191) and next prime (1131012251).

It is a cyclic number.

It is not a de Polignac number, because 1131012221 - 2¹⁸ = 1130750077 is a prime.

It is a super-3 number, since 3×1131012221³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1131012196 and 1131012205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131012251) 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, 29763461 + ... + 29763498.

It is an arithmetic number, because the mean of its divisors is an integer number (297634800).

Almost surely, 2^1131012221 is an apocalyptic number.

It is an amenable number.

1131012221 is a deficient number, since it is larger than the sum of its proper divisors (59526979).

1131012221 is an equidigital number, since it uses as much as digits as its factorization.

1131012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59526978.

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

The square root of 1131012221 is about 33630.5251371429. The cubic root of 1131012221 is about 1041.8913502687.

Adding to 1131012221 its reverse (1222101311), we get a palindrome (2353113532).

The spelling of 1131012221 in words is "one billion, one hundred thirty-one million, twelve thousand, two hundred twenty-one".