211801810947 has 16 divisors (see below), whose sum is σ = 294926258688. Its totient is φ = 134949513600.

The previous prime is 211801810921. The next prime is 211801810951. The reversal of 211801810947 is 749018108112.

It is not a de Polignac number, because 211801810947 - 2¹² = 211801806851 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211801810899 and 211801810908.

It is not an unprimeable number, because it can be changed into a prime (211801810147) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1195063 + ... + 1360800.

It is an arithmetic number, because the mean of its divisors is an integer number (18432891168).

Almost surely, 2^211801810947 is an apocalyptic number.

211801810947 is a deficient number, since it is larger than the sum of its proper divisors (83124447741).

211801810947 is a wasteful number, since it uses less digits than its factorization.

211801810947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2557090.

The product of its (nonzero) digits is 32256, while the sum is 42.

The spelling of 211801810947 in words is "two hundred eleven billion, eight hundred one million, eight hundred ten thousand, nine hundred forty-seven".