2021213131 has 4 divisors (see below), whose sum is σ = 2309957872. Its totient is φ = 1732468392.

The previous prime is 2021213093. The next prime is 2021213137. The reversal of 2021213131 is 1313121202.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2021213131 - 2¹⁵ = 2021180363 is a prime.

It is a super-2 number, since 2×2021213131² = 8170605041853646322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021213137) 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 3 ways as a sum of consecutive naturals, for example, 144372360 + ... + 144372373.

It is an arithmetic number, because the mean of its divisors is an integer number (577489468).

Almost surely, 2^2021213131 is an apocalyptic number.

2021213131 is a deficient number, since it is larger than the sum of its proper divisors (288744741).

2021213131 is an equidigital number, since it uses as much as digits as its factorization.

2021213131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288744740.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 2021213131 is about 44957.9039880642. The cubic root of 2021213131 is about 1264.3598715193.

Adding to 2021213131 its reverse (1313121202), we get a palindrome (3334334333).

The spelling of 2021213131 in words is "two billion, twenty-one million, two hundred thirteen thousand, one hundred thirty-one".