154661491 has 2 divisors, whose sum is σ = 154661492. Its totient is φ = 154661490.

The previous prime is 154661477. The next prime is 154661503. The reversal of 154661491 is 194166451.

It is a strong prime.

It is an emirp because it is prime and its reverse (194166451) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 154661491 - 2⁵ = 154661459 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 154661491.

It is not a weakly prime, because it can be changed into another prime (154661891) 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 as a sum of consecutive naturals, namely, 77330745 + 77330746.

It is an arithmetic number, because the mean of its divisors is an integer number (77330746).

Almost surely, 2^154661491 is an apocalyptic number.

154661491 is a deficient number, since it is larger than the sum of its proper divisors (1).

154661491 is an equidigital number, since it uses as much as digits as its factorization.

154661491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 37.

The square root of 154661491 is about 12436.2973187360. The cubic root of 154661491 is about 536.7772044897. Note that the first 3 decimals are identical.

The spelling of 154661491 in words is "one hundred fifty-four million, six hundred sixty-one thousand, four hundred ninety-one".