1221020031 has 64 divisors (see below), whose sum is σ = 2119633920. Its totient is φ = 606627840.

The previous prime is 1221019979. The next prime is 1221020069. The reversal of 1221020031 is 1300201221.

It is not a de Polignac number, because 1221020031 - 2⁷ = 1221019903 is a prime.

It is a super-2 number, since 2×1221020031² = 2981779832206481922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221019989 and 1221020016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221020231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 756181 + ... + 757793.

It is an arithmetic number, because the mean of its divisors is an integer number (33119280).

Almost surely, 2^1221020031 is an apocalyptic number.

1221020031 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221020031 is a deficient number, since it is larger than the sum of its proper divisors (898613889).

1221020031 is a wasteful number, since it uses less digits than its factorization.

1221020031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1776.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1221020031 is about 34943.0970436222. The cubic root of 1221020031 is about 1068.8274432169.

Adding to 1221020031 its reverse (1300201221), we get a palindrome (2521221252).

The spelling of 1221020031 in words is "one billion, two hundred twenty-one million, twenty thousand, thirty-one".