211997805751 has 2 divisors, whose sum is σ = 211997805752. Its totient is φ = 211997805750.

The previous prime is 211997805697. The next prime is 211997805787. The reversal of 211997805751 is 157508799112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211997805751 - 2¹³ = 211997797559 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211997805692 and 211997805701.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211997805451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105998902875 + 105998902876.

It is an arithmetic number, because the mean of its divisors is an integer number (105998902876).

Almost surely, 2^211997805751 is an apocalyptic number.

211997805751 is a deficient number, since it is larger than the sum of its proper divisors (1).

211997805751 is an equidigital number, since it uses as much as digits as its factorization.

211997805751 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1587600, while the sum is 55.

The spelling of 211997805751 in words is "two hundred eleven billion, nine hundred ninety-seven million, eight hundred five thousand, seven hundred fifty-one".