154660721 has 2 divisors, whose sum is σ = 154660722. Its totient is φ = 154660720.

The previous prime is 154660711. The next prime is 154660823. The reversal of 154660721 is 127066451.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91680625 + 62980096 = 9575^2 + 7936^2 .

It is a cyclic number.

It is not a de Polignac number, because 154660721 - 2⁶ = 154660657 is a prime.

It is not a weakly prime, because it can be changed into another prime (154660711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77330360 + 77330361.

It is an arithmetic number, because the mean of its divisors is an integer number (77330361).

Almost surely, 2^154660721 is an apocalyptic number.

It is an amenable number.

154660721 is a deficient number, since it is larger than the sum of its proper divisors (1).

154660721 is an equidigital number, since it uses as much as digits as its factorization.

154660721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 154660721 is about 12436.2663609300. The cubic root of 154660721 is about 536.7763136859.

The spelling of 154660721 in words is "one hundred fifty-four million, six hundred sixty thousand, seven hundred twenty-one".