212545561 has 2 divisors, whose sum is σ = 212545562. Its totient is φ = 212545560.

The previous prime is 212545513. The next prime is 212545573. The reversal of 212545561 is 165545212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 159896025 + 52649536 = 12645^2 + 7256^2 .

It is a cyclic number.

It is not a de Polignac number, because 212545561 - 2²⁷ = 78327833 is a prime.

It is not a weakly prime, because it can be changed into another prime (212545061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106272780 + 106272781.

It is an arithmetic number, because the mean of its divisors is an integer number (106272781).

Almost surely, 2^212545561 is an apocalyptic number.

It is an amenable number.

212545561 is a deficient number, since it is larger than the sum of its proper divisors (1).

212545561 is an equidigital number, since it uses as much as digits as its factorization.

212545561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12000, while the sum is 31.

The square root of 212545561 is about 14578.9423827656. The cubic root of 212545561 is about 596.7842409848.

The spelling of 212545561 in words is "two hundred twelve million, five hundred forty-five thousand, five hundred sixty-one".