212640556 has 24 divisors (see below), whose sum is σ = 394477776. Its totient is φ = 99947520.

The previous prime is 212640553. The next prime is 212640581. The reversal of 212640556 is 655046212.

It is not an unprimeable number, because it can be changed into a prime (212640553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86991 + ... + 89401.

It is an arithmetic number, because the mean of its divisors is an integer number (16436574).

Almost surely, 2^212640556 is an apocalyptic number.

It is an amenable number.

212640556 is a deficient number, since it is larger than the sum of its proper divisors (181837220).

212640556 is a wasteful number, since it uses less digits than its factorization.

212640556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3729 (or 3727 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 212640556 is about 14582.1999711978. The cubic root of 212640556 is about 596.8731365529.

Adding to 212640556 its reverse (655046212), we get a palindrome (867686768).

The spelling of 212640556 in words is "two hundred twelve million, six hundred forty thousand, five hundred fifty-six".