133681801421 has 12 divisors (see below), whose sum is σ = 156174828732. Its totient is φ = 114092612928.

The previous prime is 133681801403. The next prime is 133681801427. The reversal of 133681801421 is 124108186331.

It can be written as a sum of positive squares in 2 ways, for example, as 90453570025 + 43228231396 = 300755^2 + 207914^2 .

It is a de Polignac number, because none of the positive numbers 2^k-133681801421 is a prime.

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 (133681801427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5843090 + ... + 5865923.

It is an arithmetic number, because the mean of its divisors is an integer number (13014569061).

Almost surely, 2^133681801421 is an apocalyptic number.

It is an amenable number.

133681801421 is a deficient number, since it is larger than the sum of its proper divisors (22493027311).

133681801421 is a wasteful number, since it uses less digits than its factorization.

133681801421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11709260 (or 11709253 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 38.

Adding to 133681801421 its reverse (124108186331), we get a palindrome (257789987752).

The spelling of 133681801421 in words is "one hundred thirty-three billion, six hundred eighty-one million, eight hundred one thousand, four hundred twenty-one".