1213021020 has 48 divisors (see below), whose sum is σ = 3398038560. Its totient is φ = 323321856.

The previous prime is 1213020967. The next prime is 1213021031. The reversal of 1213021020 is 201203121.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 1213020987 and 1213021005.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196704 + ... + 202776.

It is an arithmetic number, because the mean of its divisors is an integer number (70792470).

Almost surely, 2^1213021020 is an apocalyptic number.

1213021020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1213021020 is an abundant number, since it is smaller than the sum of its proper divisors (2185017540).

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

1213021020 is a wasteful number, since it uses less digits than its factorization.

1213021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9414 (or 9412 counting only the distinct ones).

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

The square root of 1213021020 is about 34828.4513006249. The cubic root of 1213021020 is about 1066.4883332508.

Adding to 1213021020 its reverse (201203121), we get a palindrome (1414224141).

The spelling of 1213021020 in words is "one billion, two hundred thirteen million, twenty-one thousand, twenty".