1221121031 has 16 divisors (see below), whose sum is σ = 1360369920. Its totient is φ = 1088501760.

The previous prime is 1221121021. The next prime is 1221121039. The reversal of 1221121031 is 1301211221.

It is not a de Polignac number, because 1221121031 - 2¹⁰ = 1221120007 is a prime.

It is a super-2 number, since 2×1221121031² = 2982273144701005922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221120997 and 1221121015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221121039) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 202151 + ... + 208103.

It is an arithmetic number, because the mean of its divisors is an integer number (85023120).

Almost surely, 2^1221121031 is an apocalyptic number.

1221121031 is a deficient number, since it is larger than the sum of its proper divisors (139248889).

1221121031 is a wasteful number, since it uses less digits than its factorization.

1221121031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6506.

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

The square root of 1221121031 is about 34944.5422204956. The cubic root of 1221121031 is about 1068.8569127295.

Adding to 1221121031 its reverse (1301211221), we get a palindrome (2522332252).

The spelling of 1221121031 in words is "one billion, two hundred twenty-one million, one hundred twenty-one thousand, thirty-one".