1213112021 has 16 divisors (see below), whose sum is σ = 1373284800. Its totient is φ = 1061491200.

The previous prime is 1213112011. The next prime is 1213112041. The reversal of 1213112021 is 1202113121.

It is not a de Polignac number, because 1213112021 - 2⁶ = 1213111957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1213111987 and 1213112005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213112011) 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, 99845 + ... + 111333.

It is an arithmetic number, because the mean of its divisors is an integer number (85830300).

Almost surely, 2^1213112021 is an apocalyptic number.

1213112021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1213112021 is a deficient number, since it is larger than the sum of its proper divisors (160172779).

1213112021 is a wasteful number, since it uses less digits than its factorization.

1213112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11860.

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

The square root of 1213112021 is about 34829.7576936734. The cubic root of 1213112021 is about 1066.5150019499.

Adding to 1213112021 its reverse (1202113121), we get a palindrome (2415225142).

The spelling of 1213112021 in words is "one billion, two hundred thirteen million, one hundred twelve thousand, twenty-one".