211945657 has 24 divisors (see below), whose sum is σ = 273482048. Its totient is φ = 160665120.

The previous prime is 211945637. The next prime is 211945661. The reversal of 211945657 is 756549112.

It is not a de Polignac number, because 211945657 - 2²³ = 203557049 is a prime.

It is not an unprimeable number, because it can be changed into a prime (211945637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27958 + ... + 34720.

Almost surely, 2^211945657 is an apocalyptic number.

It is an amenable number.

211945657 is a deficient number, since it is larger than the sum of its proper divisors (61536391).

211945657 is a wasteful number, since it uses less digits than its factorization.

211945657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6829 (or 6818 counting only the distinct ones).

The product of its digits is 75600, while the sum is 40.

The square root of 211945657 is about 14558.3535126744. The cubic root of 211945657 is about 596.2222428760. Note that the first 4 decimals are identical.

The spelling of 211945657 in words is "two hundred eleven million, nine hundred forty-five thousand, six hundred fifty-seven".