133915661 has 6 divisors (see below), whose sum is σ = 147196686. Its totient is φ = 121741400.

The previous prime is 133915651. The next prime is 133915669. The reversal of 133915661 is 166519331.

It can be written as a sum of positive squares in only one way, i.e., 91795561 + 42120100 = 9581^2 + 6490^2 .

It is a de Polignac number, because none of the positive numbers 2^k-133915661 is a prime.

It is a super-2 number, since 2×133915661² = 35866808522133842, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133915669) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 553250 + ... + 553491.

It is an arithmetic number, because the mean of its divisors is an integer number (24532781).

Almost surely, 2^133915661 is an apocalyptic number.

133915661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

133915661 is a deficient number, since it is larger than the sum of its proper divisors (13281025).

133915661 is a wasteful number, since it uses less digits than its factorization.

133915661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1106763 (or 1106752 counting only the distinct ones).

The product of its digits is 14580, while the sum is 35.

The square root of 133915661 is about 11572.1934394479. The cubic root of 133915661 is about 511.6156134391.

The spelling of 133915661 in words is "one hundred thirty-three million, nine hundred fifteen thousand, six hundred sixty-one".