1221011031 has 8 divisors (see below), whose sum is σ = 1628248960. Its totient is φ = 813890232.

The previous prime is 1221011027. The next prime is 1221011039. The reversal of 1221011031 is 1301101221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221011031 - 2² = 1221011027 is a prime.

It is a super-2 number, since 2×1221011031² = 2981735875647365922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221010998 and 1221011016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221011039) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1075 + ... + 49428.

It is an arithmetic number, because the mean of its divisors is an integer number (203531120).

Almost surely, 2^1221011031 is an apocalyptic number.

1221011031 is a deficient number, since it is larger than the sum of its proper divisors (407237929).

1221011031 is an equidigital number, since it uses as much as digits as its factorization.

1221011031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58565.

The product of its (nonzero) digits is 12, while the sum is 12.

The square root of 1221011031 is about 34942.9682625847. The cubic root of 1221011031 is about 1068.8248171419.

Adding to 1221011031 its reverse (1301101221), we get a palindrome (2522112252).

The spelling of 1221011031 in words is "one billion, two hundred twenty-one million, eleven thousand, thirty-one".