133801621 has 16 divisors (see below), whose sum is σ = 143078400. Its totient is φ = 124905088.

The previous prime is 133801601. The next prime is 133801631. The reversal of 133801621 is 126108331.

It is not a de Polignac number, because 133801621 - 2¹⁵ = 133768853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133801601) 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 15 ways as a sum of consecutive naturals, for example, 120756 + ... + 121858.

It is an arithmetic number, because the mean of its divisors is an integer number (8942400).

Almost surely, 2^133801621 is an apocalyptic number.

It is an amenable number.

133801621 is a deficient number, since it is larger than the sum of its proper divisors (9276779).

133801621 is a wasteful number, since it uses less digits than its factorization.

133801621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1268.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 133801621 is about 11567.2650613704. The cubic root of 133801621 is about 511.4703448582.

Adding to 133801621 its reverse (126108331), we get a palindrome (259909952).

The spelling of 133801621 in words is "one hundred thirty-three million, eight hundred one thousand, six hundred twenty-one".