133685861 has 2 divisors, whose sum is σ = 133685862. Its totient is φ = 133685860.

The previous prime is 133685803. The next prime is 133685869. The reversal of 133685861 is 168586331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 91565761 + 42120100 = 9569^2 + 6490^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133685861 is a prime.

It is a super-2 number, since 2×133685861² = 35743818862622642, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (133685869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66842930 + 66842931.

It is an arithmetic number, because the mean of its divisors is an integer number (66842931).

Almost surely, 2^133685861 is an apocalyptic number.

It is an amenable number.

133685861 is a deficient number, since it is larger than the sum of its proper divisors (1).

133685861 is an equidigital number, since it uses as much as digits as its factorization.

133685861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 41.

The square root of 133685861 is about 11562.2602029188. The cubic root of 133685861 is about 511.3228008308.

The spelling of 133685861 in words is "one hundred thirty-three million, six hundred eighty-five thousand, eight hundred sixty-one".