133699661 has 2 divisors, whose sum is σ = 133699662. Its totient is φ = 133699660.

The previous prime is 133699651. The next prime is 133699663. The reversal of 133699661 is 166996331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 119486761 + 14212900 = 10931^2 + 3770^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133699661 is a prime.

It is a Sophie Germain prime.

Together with 133699663, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (133699663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66849830 + 66849831.

It is an arithmetic number, because the mean of its divisors is an integer number (66849831).

Almost surely, 2^133699661 is an apocalyptic number.

It is an amenable number.

133699661 is a deficient number, since it is larger than the sum of its proper divisors (1).

133699661 is an equidigital number, since it uses as much as digits as its factorization.

133699661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 157464, while the sum is 44.

The square root of 133699661 is about 11562.8569566522. The cubic root of 133699661 is about 511.3403943439.

The spelling of 133699661 in words is "one hundred thirty-three million, six hundred ninety-nine thousand, six hundred sixty-one".