212261706621 has 12 divisors (see below), whose sum is σ = 307049154048. Its totient is φ = 141300614664.

The previous prime is 212261706599. The next prime is 212261706641. The reversal of 212261706621 is 126607162212.

It is a happy number.

212261706621 is a `hidden beast` number, since 2 + 1 + 2 + 26 + 1 + 7 + 0 + 6 + 621 = 666.

It is not a de Polignac number, because 212261706621 - 2⁵ = 212261706589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212261706641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17259325 + ... + 17271618.

It is an arithmetic number, because the mean of its divisors is an integer number (25587429504).

Almost surely, 2^212261706621 is an apocalyptic number.

It is an amenable number.

212261706621 is a deficient number, since it is larger than the sum of its proper divisors (94787447427).

212261706621 is a wasteful number, since it uses less digits than its factorization.

212261706621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34531632 (or 34531629 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

Adding to 212261706621 its reverse (126607162212), we get a palindrome (338868868833).

The spelling of 212261706621 in words is "two hundred twelve billion, two hundred sixty-one million, seven hundred six thousand, six hundred twenty-one".