211612640 has 24 divisors (see below), whose sum is σ = 499935240. Its totient is φ = 84644992.

The previous prime is 211612613. The next prime is 211612649. The reversal of 211612640 is 46216112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211612649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 661130 + ... + 661449.

It is an arithmetic number, because the mean of its divisors is an integer number (20830635).

Almost surely, 2^211612640 is an apocalyptic number.

211612640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211612640 is an abundant number, since it is smaller than the sum of its proper divisors (288322600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

211612640 is a wasteful number, since it uses less digits than its factorization.

211612640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1322594 (or 1322586 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 211612640 is about 14546.9116997389. The cubic root of 211612640 is about 595.9098102345.

Adding to 211612640 its reverse (46216112), we get a palindrome (257828752).

The spelling of 211612640 in words is "two hundred eleven million, six hundred twelve thousand, six hundred forty".