212409481 has 2 divisors, whose sum is σ = 212409482. Its totient is φ = 212409480.

The previous prime is 212409469. The next prime is 212409511. The reversal of 212409481 is 184904212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 205205625 + 7203856 = 14325^2 + 2684^2 .

It is a cyclic number.

It is not a de Polignac number, because 212409481 - 2¹³ = 212401289 is a prime.

It is a super-2 number, since 2×212409481² = 90235575237378722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (212409401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106204740 + 106204741.

It is an arithmetic number, because the mean of its divisors is an integer number (106204741).

Almost surely, 2^212409481 is an apocalyptic number.

It is an amenable number.

212409481 is a deficient number, since it is larger than the sum of its proper divisors (1).

212409481 is an equidigital number, since it uses as much as digits as its factorization.

212409481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 212409481 is about 14574.2746303204. The cubic root of 212409481 is about 596.6568522395.

The spelling of 212409481 in words is "two hundred twelve million, four hundred nine thousand, four hundred eighty-one".