2123212156 has 24 divisors (see below), whose sum is σ = 4175416224. Its totient is φ = 937337280.

The previous prime is 2123212123. The next prime is 2123212207. The reversal of 2123212156 is 6512123212.

It is a self number, because there is not a number n which added to its sum of digits gives 2123212156.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 886435 + ... + 888826.

It is an arithmetic number, because the mean of its divisors is an integer number (173975676).

Almost surely, 2^2123212156 is an apocalyptic number.

2123212156 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

2123212156 is a deficient number, since it is larger than the sum of its proper divisors (2052204068).

2123212156 is a wasteful number, since it uses less digits than its factorization.

2123212156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1775301 (or 1775299 counting only the distinct ones).

The product of its digits is 1440, while the sum is 25.

The square root of 2123212156 is about 46078.3263150909. The cubic root of 2123212156 is about 1285.2801411964.

Adding to 2123212156 its reverse (6512123212), we get a palindrome (8635335368).

The spelling of 2123212156 in words is "two billion, one hundred twenty-three million, two hundred twelve thousand, one hundred fifty-six".