166564537 has 2 divisors, whose sum is σ = 166564538. Its totient is φ = 166564536.

The previous prime is 166564513. The next prime is 166564543. The reversal of 166564537 is 735465661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 140564736 + 25999801 = 11856^2 + 5099^2 .

It is a cyclic number.

It is not a de Polignac number, because 166564537 - 2¹¹ = 166562489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166564493 and 166564502.

It is not a weakly prime, because it can be changed into another prime (166564577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83282268 + 83282269.

It is an arithmetic number, because the mean of its divisors is an integer number (83282269).

Almost surely, 2^166564537 is an apocalyptic number.

It is an amenable number.

166564537 is a deficient number, since it is larger than the sum of its proper divisors (1).

166564537 is an equidigital number, since it uses as much as digits as its factorization.

166564537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 453600, while the sum is 43.

The square root of 166564537 is about 12905.9884162353. The cubic root of 166564537 is about 550.2087769378.

The spelling of 166564537 in words is "one hundred sixty-six million, five hundred sixty-four thousand, five hundred thirty-seven".