133525721 has 16 divisors (see below), whose sum is σ = 156326400. Its totient is φ = 111691008.

The previous prime is 133525703. The next prime is 133525729. The reversal of 133525721 is 127525331.

It is a cyclic number.

It is not a de Polignac number, because 133525721 - 2²² = 129331417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133525729) 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, 47861 + ... + 50573.

It is an arithmetic number, because the mean of its divisors is an integer number (9770400).

Almost surely, 2^133525721 is an apocalyptic number.

It is an amenable number.

133525721 is a deficient number, since it is larger than the sum of its proper divisors (22800679).

133525721 is an equidigital number, since it uses as much as digits as its factorization.

133525721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2888.

The product of its digits is 6300, while the sum is 29.

The square root of 133525721 is about 11555.3330112117. Note that the first 3 decimals coincide. The cubic root of 133525721 is about 511.1185509822.

The spelling of 133525721 in words is "one hundred thirty-three million, five hundred twenty-five thousand, seven hundred twenty-one".