211247795021956 has 81 divisors (see below), whose sum is σ = 472693772944407. Its totient is φ = 82303463660880.

The previous prime is 211247795021933. The next prime is 211247795021957. The reversal of 211247795021956 is 659120597742112.

The square root of 211247795021956 is 14534366.

It is a perfect power (a square), and thus also a powerful number.

It is a junction number, because it is equal to n+sod(n) for n = 211247795021894 and 211247795021903.

It is not an unprimeable number, because it can be changed into a prime (211247795021957) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2238245175 + ... + 2238339553.

Almost surely, 2^{211247795021956} is an apocalyptic number.

211247795021956 is the 14534366-th square number.

It is an amenable number.

211247795021956 is an abundant number, since it is smaller than the sum of its proper divisors (261445977922451).

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

211247795021956 is an frugal number, since it uses more digits than its factorization.

211247795021956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188798 (or 94399 counting only the distinct ones).

The product of its (nonzero) digits is 19051200, while the sum is 61.

The spelling of 211247795021956 in words is "two hundred eleven trillion, two hundred forty-seven billion, seven hundred ninety-five million, twenty-one thousand, nine hundred fifty-six".