2121213131 has 16 divisors (see below), whose sum is σ = 2260934208. Its totient is φ = 1983206400.

The previous prime is 2121213113. The next prime is 2121213151. The reversal of 2121213131 is 1313121212.

It is a de Polignac number, because none of the positive numbers 2^k-2121213131 is a prime.

It is a super-2 number, since 2×2121213131² = 8999090294253646322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2121213151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2225351 + ... + 2226303.

It is an arithmetic number, because the mean of its divisors is an integer number (141308388).

Almost surely, 2^2121213131 is an apocalyptic number.

2121213131 is a deficient number, since it is larger than the sum of its proper divisors (139721077).

2121213131 is a wasteful number, since it uses less digits than its factorization.

2121213131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1702.

The product of its digits is 72, while the sum is 17.

The square root of 2121213131 is about 46056.6296096447. The cubic root of 2121213131 is about 1284.8766465995.

Adding to 2121213131 its reverse (1313121212), we get a palindrome (3434334343).

It can be divided in two parts, 21212 and 13131, that added together give a palindrome (34343).

The spelling of 2121213131 in words is "two billion, one hundred twenty-one million, two hundred thirteen thousand, one hundred thirty-one".