133421220 has 36 divisors (see below), whose sum is σ = 404711580. Its totient is φ = 35578944.

The previous prime is 133421207. The next prime is 133421227. The reversal of 133421220 is 22124331.

It can be written as a sum of positive squares in 2 ways, for example, as 15872256 + 117548964 = 3984^2 + 10842^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nialpdrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 133421193 and 133421202.

It is not an unprimeable number, because it can be changed into a prime (133421227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 370435 + ... + 370794.

Almost surely, 2^133421220 is an apocalyptic number.

133421220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

133421220 is an abundant number, since it is smaller than the sum of its proper divisors (271290360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

133421220 is a wasteful number, since it uses less digits than its factorization.

133421220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741244 (or 741239 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 133421220 is about 11550.8103611825. The cubic root of 133421220 is about 510.9851775782.

Adding to 133421220 its reverse (22124331), we get a palindrome (155545551).

The spelling of 133421220 in words is "one hundred thirty-three million, four hundred twenty-one thousand, two hundred twenty".