1220311031 has 4 divisors (see below), whose sum is σ = 1220473272. Its totient is φ = 1220148792.

The previous prime is 1220311019. The next prime is 1220311049. The reversal of 1220311031 is 1301130221.

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-1220311031 is a prime.

It is a super-4 number, since 4×1220311031⁴ (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 junction number, because it is equal to n+sod(n) for n = 1220310997 and 1220311015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220311531) 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, 69260 + ... + 85073.

It is an arithmetic number, because the mean of its divisors is an integer number (305118318).

Almost surely, 2^1220311031 is an apocalyptic number.

1220311031 is a deficient number, since it is larger than the sum of its proper divisors (162241).

1220311031 is an equidigital number, since it uses as much as digits as its factorization.

1220311031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162240.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 1220311031 is about 34932.9505052178. The cubic root of 1220311031 is about 1068.6205273159.

Adding to 1220311031 its reverse (1301130221), we get a palindrome (2521441252).

The spelling of 1220311031 in words is "one billion, two hundred twenty million, three hundred eleven thousand, thirty-one".