212740081 has 2 divisors, whose sum is σ = 212740082. Its totient is φ = 212740080.

The previous prime is 212740079. The next prime is 212740097. The reversal of 212740081 is 180047212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149059681 + 63680400 = 12209^2 + 7980^2 .

It is a cyclic number.

It is not a de Polignac number, because 212740081 - 2¹ = 212740079 is a prime.

It is a super-2 number, since 2×212740081² = 90516684127773122, which contains 22 as substring.

Together with 212740079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (212740061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106370040 + 106370041.

It is an arithmetic number, because the mean of its divisors is an integer number (106370041).

Almost surely, 2^212740081 is an apocalyptic number.

It is an amenable number.

212740081 is a deficient number, since it is larger than the sum of its proper divisors (1).

212740081 is an equidigital number, since it uses as much as digits as its factorization.

212740081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 212740081 is about 14585.6121229107. The cubic root of 212740081 is about 596.9662428643.

Adding to 212740081 its reverse (180047212), we get a palindrome (392787293).

The spelling of 212740081 in words is "two hundred twelve million, seven hundred forty thousand, eighty-one".