153481721 has 8 divisors (see below), whose sum is σ = 155503488. Its totient is φ = 151470000.

The previous prime is 153481709. The next prime is 153481723. The reversal of 153481721 is 127184351.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 153481721 - 2²⁶ = 86372857 is a prime.

It is a super-2 number, since 2×153481721² = 47113277362243682, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (153481723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31136 + ... + 35726.

It is an arithmetic number, because the mean of its divisors is an integer number (19437936).

Almost surely, 2^153481721 is an apocalyptic number.

It is an amenable number.

153481721 is a deficient number, since it is larger than the sum of its proper divisors (2021767).

153481721 is a wasteful number, since it uses less digits than its factorization.

153481721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5023.

The product of its digits is 6720, while the sum is 32.

The square root of 153481721 is about 12388.7739909968. The cubic root of 153481721 is about 535.4088597313.

The spelling of 153481721 in words is "one hundred fifty-three million, four hundred eighty-one thousand, seven hundred twenty-one".