11312221031 has 4 divisors (see below), whose sum is σ = 11804056752. Its totient is φ = 10820385312.

The previous prime is 11312220853. The next prime is 11312221051. The reversal of 11312221031 is 13012221311.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11312221031 is a prime.

It is a super-2 number, since 2×11312221031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11312221051) 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, 245917826 + ... + 245917871.

It is an arithmetic number, because the mean of its divisors is an integer number (2951014188).

Almost surely, 2^11312221031 is an apocalyptic number.

11312221031 is a deficient number, since it is larger than the sum of its proper divisors (491835721).

11312221031 is an equidigital number, since it uses as much as digits as its factorization.

11312221031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491835720.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 11312221031 its reverse (13012221311), we get a palindrome (24324442342).

The spelling of 11312221031 in words is "eleven billion, three hundred twelve million, two hundred twenty-one thousand, thirty-one".