1231220020 has 12 divisors (see below), whose sum is σ = 2585562084. Its totient is φ = 492488000.

The previous prime is 1231219967. The next prime is 1231220033. The reversal of 1231220020 is 200221321.

It can be written as a sum of positive squares in 2 ways, for example, as 583415716 + 647804304 = 24154^2 + 25452^2 .

It is a super-4 number, since 4×1231220020⁴ (a number of 37 digits) contains 4444 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30780481 + ... + 30780520.

It is an arithmetic number, because the mean of its divisors is an integer number (215463507).

Almost surely, 2^1231220020 is an apocalyptic number.

1231220020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1231220020 is an abundant number, since it is smaller than the sum of its proper divisors (1354342064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1231220020 is a wasteful number, since it uses less digits than its factorization.

1231220020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61561010 (or 61561008 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 1231220020 is about 35088.7449191333. The cubic root of 1231220020 is about 1071.7954018926.

Adding to 1231220020 its reverse (200221321), we get a palindrome (1431441341).

The spelling of 1231220020 in words is "one billion, two hundred thirty-one million, two hundred twenty thousand, twenty".