154291721 has 4 divisors (see below), whose sum is σ = 154425552. Its totient is φ = 154157892.

The previous prime is 154291717. The next prime is 154291757. The reversal of 154291721 is 127192451.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 154291721 - 2² = 154291717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (154291421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65171 + ... + 67496.

It is an arithmetic number, because the mean of its divisors is an integer number (38606388).

Almost surely, 2^154291721 is an apocalyptic number.

It is an amenable number.

154291721 is a deficient number, since it is larger than the sum of its proper divisors (133831).

154291721 is a wasteful number, since it uses less digits than its factorization.

154291721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133830.

The product of its digits is 5040, while the sum is 32.

The square root of 154291721 is about 12421.4218590305. The cubic root of 154291721 is about 536.3490813309.

The spelling of 154291721 in words is "one hundred fifty-four million, two hundred ninety-one thousand, seven hundred twenty-one".